SQLiteDatabase


public final class SQLiteDatabase
extends SQLiteClosable

java.lang.Object
   ↳ android.database.sqlite.SQLiteClosable
     ↳ android.database.sqlite.SQLiteDatabase


Exposes methods to manage a SQLite database.

SQLiteDatabase has methods to create, delete, execute SQL commands, and perform other common database management tasks.

See the Notepad sample application in the SDK for an example of creating and managing a database.

Database names must be unique within an application, not across all applications.

Localized Collation - ORDER BY

In addition to SQLite's default BINARY collator, Android supplies two more, LOCALIZED, which changes with the system's current locale, and UNICODE, which is the Unicode Collation Algorithm and not tailored to the current locale.

Summary

Nested classes

interface SQLiteDatabase.CursorFactory

Used to allow returning sub-classes of Cursor when calling query. 

class SQLiteDatabase.OpenParams

Wrapper for configuration parameters that are used for opening SQLiteDatabase 

Constants

int CONFLICT_ABORT

When a constraint violation occurs,no ROLLBACK is executed so changes from prior commands within the same transaction are preserved.

int CONFLICT_FAIL

When a constraint violation occurs, the command aborts with a return code SQLITE_CONSTRAINT.

int CONFLICT_IGNORE

When a constraint violation occurs, the one row that contains the constraint violation is not inserted or changed.

int CONFLICT_NONE

Use the following when no conflict action is specified.

int CONFLICT_REPLACE

When a UNIQUE constraint violation occurs, the pre-existing rows that are causing the constraint violation are removed prior to inserting or updating the current row.

int CONFLICT_ROLLBACK

When a constraint violation occurs, an immediate ROLLBACK occurs, thus ending the current transaction, and the command aborts with a return code of SQLITE_CONSTRAINT.

int CREATE_IF_NECESSARY

Open flag: Flag for openDatabase(File, OpenParams) to create the database file if it does not already exist.

int ENABLE_WRITE_AHEAD_LOGGING

Open flag: Flag for openDatabase(File, OpenParams) to open the database file with write-ahead logging enabled by default.

String JOURNAL_MODE_DELETE

The DELETE journaling mode is the normal behavior.

String JOURNAL_MODE_MEMORY

The MEMORY journaling mode stores the rollback journal in volatile RAM.

String JOURNAL_MODE_OFF

The OFF journaling mode disables the rollback journal completely.

String JOURNAL_MODE_PERSIST

The PERSIST journaling mode prevents the rollback journal from being deleted at the end of each transaction.

String JOURNAL_MODE_TRUNCATE

The TRUNCATE journaling mode commits transactions by truncating the rollback journal to zero-length instead of deleting it.

String JOURNAL_MODE_WAL

The WAL journaling mode uses a write-ahead log instead of a rollback journal to implement transactions.

int MAX_SQL_CACHE_SIZE

Absolute max value that can be set by setMaxSqlCacheSize(int).

int NO_LOCALIZED_COLLATORS

Open flag: Flag for openDatabase(File, OpenParams) to open the database without support for localized collators.

int OPEN_READONLY

Open flag: Flag for openDatabase(File, OpenParams) to open the database for reading only.

int OPEN_READWRITE

Open flag: Flag for openDatabase(File, OpenParams) to open the database for reading and writing. If the disk is full, this may fail even before you actually write anything.

int SQLITE_MAX_LIKE_PATTERN_LENGTH

Maximum Length Of A LIKE Or GLOB Pattern The pattern matching algorithm used in the default LIKE and GLOB implementation of SQLite can exhibit O(N^2) performance (where N is the number of characters in the pattern) for certain pathological cases.

String SYNC_MODE_EXTRA

The EXTRA sync mode is like FULL sync mode with the addition that the directory containing a rollback journal is synced after that journal is unlinked to commit a transaction in DELETE journal mode.

String SYNC_MODE_FULL

In FULL sync mode the SQLite database engine will use the xSync method of the VFS to ensure that all content is safely written to the disk surface prior to continuing.

String SYNC_MODE_NORMAL

The NORMAL sync mode, the SQLite database engine will still sync at the most critical moments, but less often than in FULL mode.

String SYNC_MODE_OFF

In OFF sync mode SQLite continues without syncing as soon as it has handed data off to the operating system.

Public methods

void beginTransaction()

Begins a transaction in EXCLUSIVE mode.

void beginTransactionNonExclusive()

Begins a transaction in IMMEDIATE mode.

void beginTransactionReadOnly()

Begins a transaction in DEFERRED mode, with the android-specific constraint that the transaction is read-only.

void beginTransactionWithListener(SQLiteTransactionListener transactionListener)

Begins a transaction in EXCLUSIVE mode.

void beginTransactionWithListenerNonExclusive(SQLiteTransactionListener transactionListener)

Begins a transaction in IMMEDIATE mode.

void beginTransactionWithListenerReadOnly(SQLiteTransactionListener transactionListener)

Begins a transaction in read-only mode with a SQLiteTransactionListener listener.

SQLiteStatement compileStatement(String sql)

Compiles an SQL statement into a reusable pre-compiled statement object.

static SQLiteDatabase create(SQLiteDatabase.CursorFactory factory)

Create a memory backed SQLite database.

static SQLiteDatabase createInMemory(SQLiteDatabase.OpenParams openParams)

Create a memory backed SQLite database.

SQLiteRawStatement createRawStatement(String sql)

Return a SQLiteRawStatement connected to the database.

int delete(String table, String whereClause, String[] whereArgs)

Convenience method for deleting rows in the database.

static boolean deleteDatabase(File file)

Deletes a database including its journal file and other auxiliary files that may have been created by the database engine.

void disableWriteAheadLogging()

This method disables the features enabled by enableWriteAheadLogging().

boolean enableWriteAheadLogging()

This method enables parallel execution of queries from multiple threads on the same database.

void endTransaction()

End a transaction.

void execPerConnectionSQL(String sql, Object[] bindArgs)

Execute the given SQL statement on all connections to this database.

void execSQL(String sql)

Execute a single SQL statement that is NOT a SELECT or any other SQL statement that returns data.

void execSQL(String sql, Object[] bindArgs)

Execute a single SQL statement that is NOT a SELECT/INSERT/UPDATE/DELETE.

static String findEditTable(String tables)

Finds the name of the first table, which is editable.

List<Pair<StringString>> getAttachedDbs()

Returns list of full pathnames of all attached databases including the main database by executing 'pragma database_list' on the database.

long getLastChangedRowCount()

Return the number of database rows that were inserted, updated, or deleted by the most recent SQL statement within the current transaction.

long getLastInsertRowId()

Return the "rowid" of the last row to be inserted on the current connection.

long getMaximumSize()

Returns the maximum size the database may grow to.

long getPageSize()

Returns the current database page size, in bytes.

String getPath()

Gets the path to the database file.

Map<StringString> getSyncedTables()

This method was deprecated in API level 15. This method no longer serves any useful purpose and has been deprecated.

long getTotalChangedRowCount()

Return the total number of database rows that have been inserted, updated, or deleted on the current connection since it was created.

int getVersion()

Gets the database version.

boolean inTransaction()

Returns true if the current thread has a transaction pending.

long insert(String table, String nullColumnHack, ContentValues values)

Convenience method for inserting a row into the database.

long insertOrThrow(String table, String nullColumnHack, ContentValues values)

Convenience method for inserting a row into the database.

long insertWithOnConflict(String table, String nullColumnHack, ContentValues initialValues, int conflictAlgorithm)

General method for inserting a row into the database.

boolean isDatabaseIntegrityOk()

Runs 'pragma integrity_check' on the given database (and all the attached databases) and returns true if the given database (and all its attached databases) pass integrity_check, false otherwise.

boolean isDbLockedByCurrentThread()

Returns true if the current thread is holding an active connection to the database.

boolean isDbLockedByOtherThreads()

This method was deprecated in API level 16. Always returns false. Do not use this method.

boolean isOpen()

Returns true if the database is currently open.

boolean isReadOnly()

Returns true if the database is opened as read only.

boolean isWriteAheadLoggingEnabled()

Returns true if write-ahead logging has been enabled for this database.

void markTableSyncable(String table, String deletedTable)

This method was deprecated in API level 15. This method no longer serves any useful purpose and has been deprecated.

void markTableSyncable(String table, String foreignKey, String updateTable)

This method was deprecated in API level 15. This method no longer serves any useful purpose and has been deprecated.

boolean needUpgrade(int newVersion)

Returns true if the new version code is greater than the current database version.

static SQLiteDatabase openDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags)

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY and/or NO_LOCALIZED_COLLATORS.

static SQLiteDatabase openDatabase(File path, SQLiteDatabase.OpenParams openParams)

Open the database according to the specified parameters

static SQLiteDatabase openDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags, DatabaseErrorHandler errorHandler)

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY and/or NO_LOCALIZED_COLLATORS.

static SQLiteDatabase openOrCreateDatabase(File file, SQLiteDatabase.CursorFactory factory)

Equivalent to openDatabase(file.getPath(), factory, CREATE_IF_NECESSARY).

static SQLiteDatabase openOrCreateDatabase(String path, SQLiteDatabase.CursorFactory factory, DatabaseErrorHandler errorHandler)

Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY, errorHandler).

static SQLiteDatabase openOrCreateDatabase(String path, SQLiteDatabase.CursorFactory factory)

Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY).

Cursor query(boolean distinct, String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit)

Query the given URL, returning a Cursor over the result set.

Cursor query(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit)

Query the given table, returning a Cursor over the result set.

Cursor query(boolean distinct, String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit, CancellationSignal cancellationSignal)

Query the given URL, returning a Cursor over the result set.

Cursor query(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy)

Query the given table, returning a Cursor over the result set.

Cursor queryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, boolean distinct, String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit, CancellationSignal cancellationSignal)

Query the given URL, returning a Cursor over the result set.

Cursor queryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, boolean distinct, String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit)

Query the given URL, returning a Cursor over the result set.

Cursor rawQuery(String sql, String[] selectionArgs, CancellationSignal cancellationSignal)

Runs the provided SQL and returns a Cursor over the result set.

Cursor rawQuery(String sql, String[] selectionArgs)

Runs the provided SQL and returns a Cursor over the result set.

Cursor rawQueryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, String sql, String[] selectionArgs, String editTable, CancellationSignal cancellationSignal)

Runs the provided SQL and returns a cursor over the result set.

Cursor rawQueryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, String sql, String[] selectionArgs, String editTable)

Runs the provided SQL and returns a cursor over the result set.

static int releaseMemory()

Attempts to release memory that SQLite holds but does not require to operate properly.

long replace(String table, String nullColumnHack, ContentValues initialValues)

Convenience method for replacing a row in the database.

long replaceOrThrow(String table, String nullColumnHack, ContentValues initialValues)

Convenience method for replacing a row in the database.

void setCustomAggregateFunction(String functionName, BinaryOperator<String> aggregateFunction)

Register a custom aggregate function that can be called from SQL expressions.

void setCustomScalarFunction(String functionName, UnaryOperator<String> scalarFunction)

Register a custom scalar function that can be called from SQL expressions.

void setForeignKeyConstraintsEnabled(boolean enable)

Sets whether foreign key constraints are enabled for the database.

void setLocale(Locale locale)

Sets the locale for this database.

void setLockingEnabled(boolean lockingEnabled)

This method was deprecated in API level 16. This method now does nothing. Do not use.

void setMaxSqlCacheSize(int cacheSize)

Sets the maximum size of the prepared-statement cache for this database.

long setMaximumSize(long numBytes)

Sets the maximum size the database will grow to.

void setPageSize(long numBytes)

Sets the database page size.

void setTransactionSuccessful()

Marks the current transaction as successful.

void setVersion(int version)

Sets the database version.

String toString()

Returns a string representation of the object.

int update(String table, ContentValues values, String whereClause, String[] whereArgs)

Convenience method for updating rows in the database.

int updateWithOnConflict(String table, ContentValues values, String whereClause, String[] whereArgs, int conflictAlgorithm)

Convenience method for updating rows in the database.

void validateSql(String sql, CancellationSignal cancellationSignal)

Verifies that a SQL SELECT statement is valid by compiling it.

boolean yieldIfContended()

This method was deprecated in API level 15. if the db is locked more than once (because of nested transactions) then the lock will not be yielded. Use yieldIfContendedSafely instead.

boolean yieldIfContendedSafely()

Temporarily end the transaction to let other threads run.

boolean yieldIfContendedSafely(long sleepAfterYieldDelay)

Temporarily end the transaction to let other threads run.

Protected methods

void finalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

void onAllReferencesReleased()

Called when the last reference to the object was released by a call to releaseReference() or close().

Inherited methods

Constants

CONFLICT_ABORT

Added in API level 8
public static final int CONFLICT_ABORT

When a constraint violation occurs,no ROLLBACK is executed so changes from prior commands within the same transaction are preserved. This is the default behavior.

Constant Value: 2 (0x00000002)

CONFLICT_FAIL

Added in API level 8
public static final int CONFLICT_FAIL

When a constraint violation occurs, the command aborts with a return code SQLITE_CONSTRAINT. But any changes to the database that the command made prior to encountering the constraint violation are preserved and are not backed out.

Constant Value: 3 (0x00000003)

CONFLICT_IGNORE

Added in API level 8
public static final int CONFLICT_IGNORE

When a constraint violation occurs, the one row that contains the constraint violation is not inserted or changed. But the command continues executing normally. Other rows before and after the row that contained the constraint violation continue to be inserted or updated normally. No error is returned.

Constant Value: 4 (0x00000004)

CONFLICT_NONE

Added in API level 8
public static final int CONFLICT_NONE

Use the following when no conflict action is specified.

Constant Value: 0 (0x00000000)

CONFLICT_REPLACE

Added in API level 8
public static final int CONFLICT_REPLACE

When a UNIQUE constraint violation occurs, the pre-existing rows that are causing the constraint violation are removed prior to inserting or updating the current row. Thus the insert or update always occurs. The command continues executing normally. No error is returned. If a NOT NULL constraint violation occurs, the NULL value is replaced by the default value for that column. If the column has no default value, then the ABORT algorithm is used. If a CHECK constraint violation occurs then the IGNORE algorithm is used. When this conflict resolution strategy deletes rows in order to satisfy a constraint, it does not invoke delete triggers on those rows. This behavior might change in a future release.

Constant Value: 5 (0x00000005)

CONFLICT_ROLLBACK

Added in API level 8
public static final int CONFLICT_ROLLBACK

When a constraint violation occurs, an immediate ROLLBACK occurs, thus ending the current transaction, and the command aborts with a return code of SQLITE_CONSTRAINT. If no transaction is active (other than the implied transaction that is created on every command) then this algorithm works the same as ABORT.

Constant Value: 1 (0x00000001)

CREATE_IF_NECESSARY

Added in API level 1
public static final int CREATE_IF_NECESSARY

Open flag: Flag for openDatabase(File, OpenParams) to create the database file if it does not already exist.

Constant Value: 268435456 (0x10000000)

ENABLE_WRITE_AHEAD_LOGGING

Added in API level 16
public static final int ENABLE_WRITE_AHEAD_LOGGING

Open flag: Flag for openDatabase(File, OpenParams) to open the database file with write-ahead logging enabled by default. Using this flag is more efficient than calling enableWriteAheadLogging(). Write-ahead logging cannot be used with read-only databases so the value of this flag is ignored if the database is opened read-only.

Constant Value: 536870912 (0x20000000)

JOURNAL_MODE_DELETE

Added in API level 33
public static final String JOURNAL_MODE_DELETE

The DELETE journaling mode is the normal behavior. In the DELETE mode, the rollback journal is deleted at the conclusion of each transaction.

See here for more details.

Constant Value: "DELETE"

JOURNAL_MODE_MEMORY

Added in API level 33
public static final String JOURNAL_MODE_MEMORY

The MEMORY journaling mode stores the rollback journal in volatile RAM. This saves disk I/O but at the expense of database safety and integrity. If the application using SQLite crashes in the middle of a transaction when the MEMORY journaling mode is set, then the database file will very likely go corrupt.

See here for more details.

Constant Value: "MEMORY"

JOURNAL_MODE_OFF

Added in API level 33
public static final String JOURNAL_MODE_OFF

The OFF journaling mode disables the rollback journal completely. No rollback journal is ever created and hence there is never a rollback journal to delete. The OFF journaling mode disables the atomic commit and rollback capabilities of SQLite. The ROLLBACK command behaves in an undefined way thus applications must avoid using the ROLLBACK command. If the application crashes in the middle of a transaction, then the database file will very likely go corrupt.

See here for more details.

Constant Value: "OFF"

JOURNAL_MODE_PERSIST

Added in API level 33
public static final String JOURNAL_MODE_PERSIST

The PERSIST journaling mode prevents the rollback journal from being deleted at the end of each transaction. Instead, the header of the journal is overwritten with zeros. This will prevent other database connections from rolling the journal back. This mode is useful as an optimization on platforms where deleting or truncating a file is much more expensive than overwriting the first block of a file with zeros.

See here for more details.

Constant Value: "PERSIST"

JOURNAL_MODE_TRUNCATE

Added in API level 33
public static final String JOURNAL_MODE_TRUNCATE

The TRUNCATE journaling mode commits transactions by truncating the rollback journal to zero-length instead of deleting it. On many systems, truncating a file is much faster than deleting the file since the containing directory does not need to be changed.

See here for more details.

Constant Value: "TRUNCATE"

JOURNAL_MODE_WAL

Added in API level 33
public static final String JOURNAL_MODE_WAL

The WAL journaling mode uses a write-ahead log instead of a rollback journal to implement transactions. The WAL journaling mode is persistent; after being set it stays in effect across multiple database connections and after closing and reopening the database. Performance Considerations: This mode is recommended when the goal is to improve write performance or parallel read/write performance. However, it is important to note that WAL introduces checkpoints which commit all transactions that have not been synced to the database thus to maximize read performance and lower checkpointing cost a small journal size is recommended. However, other modes such as DELETE will not perform checkpoints, so it is a trade off that needs to be considered as part of the decision of which journal mode to use.

See here for more details.

Constant Value: "WAL"

MAX_SQL_CACHE_SIZE

Added in API level 11
public static final int MAX_SQL_CACHE_SIZE

Absolute max value that can be set by setMaxSqlCacheSize(int). Each prepared-statement is between 1K - 6K, depending on the complexity of the SQL statement & schema. A large SQL cache may use a significant amount of memory.

Constant Value: 100 (0x00000064)

NO_LOCALIZED_COLLATORS

Added in API level 1
public static final int NO_LOCALIZED_COLLATORS

Open flag: Flag for openDatabase(File, OpenParams) to open the database without support for localized collators.

This causes the collator LOCALIZED not to be created. You must be consistent when using this flag to use the setting the database was created with. If this is set, setLocale(Locale) will do nothing.

Constant Value: 16 (0x00000010)

OPEN_READONLY

Added in API level 1
public static final int OPEN_READONLY

Open flag: Flag for openDatabase(File, OpenParams) to open the database for reading only. This is the only reliable way to open a database if the disk may be full.

Constant Value: 1 (0x00000001)

OPEN_READWRITE

Added in API level 1
public static final int OPEN_READWRITE

Open flag: Flag for openDatabase(File, OpenParams) to open the database for reading and writing. If the disk is full, this may fail even before you actually write anything.

Note that the value of this flag is 0, so it is the default.

Constant Value: 0 (0x00000000)

SQLITE_MAX_LIKE_PATTERN_LENGTH

Added in API level 1
public static final int SQLITE_MAX_LIKE_PATTERN_LENGTH

Maximum Length Of A LIKE Or GLOB Pattern The pattern matching algorithm used in the default LIKE and GLOB implementation of SQLite can exhibit O(N^2) performance (where N is the number of characters in the pattern) for certain pathological cases. To avoid denial-of-service attacks the length of the LIKE or GLOB pattern is limited to SQLITE_MAX_LIKE_PATTERN_LENGTH bytes. The default value of this limit is 50000. A modern workstation can evaluate even a pathological LIKE or GLOB pattern of 50000 bytes relatively quickly. The denial of service problem only comes into play when the pattern length gets into millions of bytes. Nevertheless, since most useful LIKE or GLOB patterns are at most a few dozen bytes in length, cautious application developers may want to reduce this parameter to something in the range of a few hundred if they know that external users are able to generate arbitrary patterns.

Constant Value: 50000 (0x0000c350)

SYNC_MODE_EXTRA

Added in API level 33
public static final String SYNC_MODE_EXTRA

The EXTRA sync mode is like FULL sync mode with the addition that the directory containing a rollback journal is synced after that journal is unlinked to commit a transaction in DELETE journal mode. EXTRA provides additional durability if the commit is followed closely by a power loss.

See here for more details.

Constant Value: "EXTRA"

SYNC_MODE_FULL

Added in API level 33
public static final String SYNC_MODE_FULL

In FULL sync mode the SQLite database engine will use the xSync method of the VFS to ensure that all content is safely written to the disk surface prior to continuing. This ensures that an operating system crash or power failure will not corrupt the database. FULL is very safe, but it is also slower. FULL is the most commonly used synchronous setting when not in WAL mode.

See here for more details.

Constant Value: "FULL"

SYNC_MODE_NORMAL

Added in API level 33
public static final String SYNC_MODE_NORMAL

The NORMAL sync mode, the SQLite database engine will still sync at the most critical moments, but less often than in FULL mode. There is a very small chance that a power failure at the wrong time could corrupt the database in DELETE journal mode on an older filesystem. WAL journal mode is safe from corruption with NORMAL sync mode, and probably DELETE sync mode is safe too on modern filesystems. WAL mode is always consistent with NORMAL sync mode, but WAL mode does lose durability. A transaction committed in WAL mode with NORMAL might roll back following a power loss or system crash. Transactions are durable across application crashes regardless of the synchronous setting or journal mode. The NORMAL sync mode is a good choice for most applications running in WAL mode.

Caveat: Even though this sync mode is safe Be careful when using NORMAL sync mode when dealing with data dependencies between multiple databases, unless those databases use the same durability or are somehow synced, there could be corruption.

See here for more details.

Constant Value: "NORMAL"

SYNC_MODE_OFF

Added in API level 33
public static final String SYNC_MODE_OFF

In OFF sync mode SQLite continues without syncing as soon as it has handed data off to the operating system. If the application running SQLite crashes, the data will be safe, but the database might become corrupted if the operating system crashes or the computer loses power before that data has been written to the disk surface. On the other hand, commits can be orders of magnitude faster with synchronous OFF.

See here for more details.

Constant Value: "OFF"

Public methods

beginTransaction

Added in API level 1
public void beginTransaction ()

Begins a transaction in EXCLUSIVE mode.

Transactions can be nested. When the outer transaction is ended all of the work done in that transaction and all of the nested transactions will be committed or rolled back. The changes will be rolled back if any transaction is ended without being marked as clean (by calling setTransactionSuccessful). Otherwise they will be committed.

Here is the standard idiom for transactions:

   db.beginTransaction();
   try {
     ...
     db.setTransactionSuccessful();
   } finally {
     db.endTransaction();
   }
 

beginTransactionNonExclusive

Added in API level 11
public void beginTransactionNonExclusive ()

Begins a transaction in IMMEDIATE mode. Transactions can be nested. When the outer transaction is ended all of the work done in that transaction and all of the nested transactions will be committed or rolled back. The changes will be rolled back if any transaction is ended without being marked as clean (by calling setTransactionSuccessful). Otherwise they will be committed.

Here is the standard idiom for transactions:

   db.beginTransactionNonExclusive();
   try {
     ...
     db.setTransactionSuccessful();
   } finally {
     db.endTransaction();
   }
 

beginTransactionReadOnly

Added in API level 35
public void beginTransactionReadOnly ()

Begins a transaction in DEFERRED mode, with the android-specific constraint that the transaction is read-only. The database may not be modified inside a read-only transaction.

Read-only transactions may run concurrently with other read-only transactions, and if the database is in WAL mode, they may also run concurrently with IMMEDIATE or EXCLUSIVE transactions. The temp schema may be modified during a read-only transaction; if the transaction is setTransactionSuccessful(), modifications to temp tables may be visible to some subsequent transactions.

Transactions can be nested. However, the behavior of the transaction is not altered by nested transactions. A nested transaction may be any of the three transaction types but if the outermost type is read-only then nested transactions remain read-only, regardless of how they are started.

Here is the standard idiom for read-only transactions:

   db.beginTransactionReadOnly();
   try {
     ...
   } finally {
     db.endTransaction();
   }
 

beginTransactionWithListener

Added in API level 5
public void beginTransactionWithListener (SQLiteTransactionListener transactionListener)

Begins a transaction in EXCLUSIVE mode.

Transactions can be nested. When the outer transaction is ended all of the work done in that transaction and all of the nested transactions will be committed or rolled back. The changes will be rolled back if any transaction is ended without being marked as clean (by calling setTransactionSuccessful). Otherwise they will be committed.

Here is the standard idiom for transactions:

   db.beginTransactionWithListener(listener);
   try {
     ...
     db.setTransactionSuccessful();
   } finally {
     db.endTransaction();
   }
 

Parameters
transactionListener SQLiteTransactionListener: listener that should be notified when the transaction begins, commits, or is rolled back, either explicitly or by a call to yieldIfContendedSafely(). This value may be null.

beginTransactionWithListenerNonExclusive

Added in API level 11
public void beginTransactionWithListenerNonExclusive (SQLiteTransactionListener transactionListener)

Begins a transaction in IMMEDIATE mode. Transactions can be nested. When the outer transaction is ended all of the work done in that transaction and all of the nested transactions will be committed or rolled back. The changes will be rolled back if any transaction is ended without being marked as clean (by calling setTransactionSuccessful). Otherwise they will be committed.

Here is the standard idiom for transactions:

   db.beginTransactionWithListenerNonExclusive(listener);
   try {
     ...
     db.setTransactionSuccessful();
   } finally {
     db.endTransaction();
   }
 

Parameters
transactionListener SQLiteTransactionListener: listener that should be notified when the transaction begins, commits, or is rolled back, either explicitly or by a call to yieldIfContendedSafely(). This value may be null.

beginTransactionWithListenerReadOnly

Added in API level 35
public void beginTransactionWithListenerReadOnly (SQLiteTransactionListener transactionListener)

Begins a transaction in read-only mode with a SQLiteTransactionListener listener. The database may not be updated inside a read-only transaction.

Transactions can be nested. However, the behavior of the transaction is not altered by nested transactions. A nested transaction may be any of the three transaction types but if the outermost type is read-only then nested transactions remain read-only, regardless of how they are started.

Here is the standard idiom for read-only transactions:

   db.beginTransactionWightListenerReadOnly(listener);
   try {
     ...
   } finally {
     db.endTransaction();
   }
 

Parameters
transactionListener SQLiteTransactionListener: This value may be null.

compileStatement

Added in API level 1
public SQLiteStatement compileStatement (String sql)

Compiles an SQL statement into a reusable pre-compiled statement object. The parameters are identical to execSQL(java.lang.String). You may put ?s in the statement and fill in those values with SQLiteProgram#bindString and SQLiteProgram#bindLong each time you want to run the statement. Statements may not return result sets larger than 1x1.

No two threads should be using the same SQLiteStatement at the same time.

Parameters
sql String: The raw SQL statement, may contain ? for unknown values to be bound later.

Returns
SQLiteStatement A pre-compiled SQLiteStatement object. Note that SQLiteStatements are not synchronized, see the documentation for more details.

Throws
SQLException

create

Added in API level 1
public static SQLiteDatabase create (SQLiteDatabase.CursorFactory factory)

Create a memory backed SQLite database. Its contents will be destroyed when the database is closed.

Sets the locale of the database to the system's current locale. Call setLocale(Locale) if you would like something else.

Parameters
factory SQLiteDatabase.CursorFactory: an optional factory class that is called to instantiate a cursor when query is called This value may be null.

Returns
SQLiteDatabase a SQLiteDatabase instance This value cannot be null.

Throws
SQLiteException if the database cannot be created

createInMemory

Added in API level 27
public static SQLiteDatabase createInMemory (SQLiteDatabase.OpenParams openParams)

Create a memory backed SQLite database. Its contents will be destroyed when the database is closed.

Sets the locale of the database to the system's current locale. Call setLocale(Locale) if you would like something else.

Parameters
openParams SQLiteDatabase.OpenParams: configuration parameters that are used for opening SQLiteDatabase This value cannot be null.

Returns
SQLiteDatabase a SQLiteDatabase instance This value cannot be null.

Throws
SQLException if the database cannot be created

createRawStatement

Added in API level 35
public SQLiteRawStatement createRawStatement (String sql)

Return a SQLiteRawStatement connected to the database. A transaction must be in progress or an exception will be thrown. The resulting object will be closed automatically when the current transaction closes.

Parameters
sql String: The SQL string to be compiled into a prepared statement. This value cannot be null.

Returns
SQLiteRawStatement A SQLiteRawStatement holding the compiled SQL. This value cannot be null.

Throws
IllegalStateException if a transaction is not in progress.
SQLiteException if the SQL cannot be compiled.

delete

Added in API level 1
public int delete (String table, 
                String whereClause, 
                String[] whereArgs)

Convenience method for deleting rows in the database.

Parameters
table String: the table to delete from This value cannot be null.

whereClause String: the optional WHERE clause to apply when deleting. Passing null will delete all rows.

whereArgs String: You may include ?s in the where clause, which will be replaced by the values from whereArgs. The values will be bound as Strings. If whereClause is null or does not contain ?s then whereArgs may be null.

Returns
int the number of rows affected if a whereClause is passed in, 0 otherwise. To remove all rows and get a count pass "1" as the whereClause.

deleteDatabase

Added in API level 16
public static boolean deleteDatabase (File file)

Deletes a database including its journal file and other auxiliary files that may have been created by the database engine.

Parameters
file File: The database file path. This value cannot be null.

Returns
boolean True if the database was successfully deleted.

disableWriteAheadLogging

Added in API level 16
public void disableWriteAheadLogging ()

This method disables the features enabled by enableWriteAheadLogging().

Throws
IllegalStateException if there are transactions in progress at the time this method is called. WAL mode can only be changed when there are no transactions in progress.

enableWriteAheadLogging

Added in API level 11
public boolean enableWriteAheadLogging ()

This method enables parallel execution of queries from multiple threads on the same database. It does this by opening multiple connections to the database and using a different database connection for each query. The database journal mode is also changed to enable writes to proceed concurrently with reads.

When write-ahead logging is not enabled (the default), it is not possible for reads and writes to occur on the database at the same time. Before modifying the database, the writer implicitly acquires an exclusive lock on the database which prevents readers from accessing the database until the write is completed.

In contrast, when write-ahead logging is enabled (by calling this method), write operations occur in a separate log file which allows reads to proceed concurrently. While a write is in progress, readers on other threads will perceive the state of the database as it was before the write began. When the write completes, readers on other threads will then perceive the new state of the database.

It is a good idea to enable write-ahead logging whenever a database will be concurrently accessed and modified by multiple threads at the same time. However, write-ahead logging uses significantly more memory than ordinary journaling because there are multiple connections to the same database. So if a database will only be used by a single thread, or if optimizing concurrency is not very important, then write-ahead logging should be disabled.

After calling this method, execution of queries in parallel is enabled as long as the database remains open. To disable execution of queries in parallel, either call disableWriteAheadLogging() or close the database and reopen it.

The maximum number of connections used to execute queries in parallel is dependent upon the device memory and possibly other properties.

If a query is part of a transaction, then it is executed on the same database handle the transaction was begun.

Writers should use beginTransactionNonExclusive() or beginTransactionWithListenerNonExclusive(android.database.sqlite.SQLiteTransactionListener) to start a transaction. Non-exclusive mode allows database file to be in readable by other threads executing queries.

If the database has any attached databases, then execution of queries in parallel is NOT possible. Likewise, write-ahead logging is not supported for read-only databases or memory databases. In such cases, enableWriteAheadLogging() returns false.

The best way to enable write-ahead logging is to pass the ENABLE_WRITE_AHEAD_LOGGING flag to openDatabase(File, OpenParams). This is more efficient than calling enableWriteAheadLogging().

     SQLiteDatabase db = SQLiteDatabase.openDatabase("db_filename", cursorFactory,
             SQLiteDatabase.CREATE_IF_NECESSARY | SQLiteDatabase.ENABLE_WRITE_AHEAD_LOGGING,
             myDatabaseErrorHandler);
 

Another way to enable write-ahead logging is to call enableWriteAheadLogging() after opening the database.

     SQLiteDatabase db = SQLiteDatabase.openDatabase("db_filename", cursorFactory,
             SQLiteDatabase.CREATE_IF_NECESSARY, myDatabaseErrorHandler);
     db.enableWriteAheadLogging();
 

See also SQLite Write-Ahead Logging for more details about how write-ahead logging works.

Returns
boolean True if write-ahead logging is enabled.

Throws
IllegalStateException if there are transactions in progress at the time this method is called. WAL mode can only be changed when there are no transactions in progress.

endTransaction

Added in API level 1
public void endTransaction ()

End a transaction. See beginTransaction for notes about how to use this and when transactions are committed and rolled back.

execPerConnectionSQL

Added in API level 30
public void execPerConnectionSQL (String sql, 
                Object[] bindArgs)

Execute the given SQL statement on all connections to this database.

This statement will be immediately executed on all existing connections, and will be automatically executed on all future connections.

Some example usages are changes like PRAGMA trusted_schema=OFF or functions like SELECT icu_load_collation(). If you execute these statements using execSQL(String) then they will only apply to a single database connection; using this method will ensure that they are uniformly applied to all current and future connections.

Parameters
sql String: The SQL statement to be executed. Multiple statements separated by semicolons are not supported. This value cannot be null.

bindArgs Object: The arguments that should be bound to the SQL statement. This value may be null.

Throws
SQLException

execSQL

Added in API level 1
public void execSQL (String sql)

Execute a single SQL statement that is NOT a SELECT or any other SQL statement that returns data.

It has no means to return any data (such as the number of affected rows). Instead, you're encouraged to use insert(java.lang.String, java.lang.String, android.content.ContentValues), update(java.lang.String, android.content.ContentValues, java.lang.String, java.lang.String[]), et al, when possible.

When using enableWriteAheadLogging(), journal_mode is automatically managed by this class. So, do not set journal_mode using "PRAGMA journal_mode'" statement if your app is using enableWriteAheadLogging()

Note that PRAGMA values which apply on a per-connection basis should not be configured using this method; you should instead use execPerConnectionSQL(String, Object) to ensure that they are uniformly applied to all current and future connections.

Parameters
sql String: the SQL statement to be executed. Multiple statements separated by semicolons are not supported.

Throws
SQLException if the SQL string is invalid

execSQL

Added in API level 1
public void execSQL (String sql, 
                Object[] bindArgs)

Execute a single SQL statement that is NOT a SELECT/INSERT/UPDATE/DELETE.

For INSERT statements, use any of the following instead.

For UPDATE statements, use any of the following instead.

For DELETE statements, use any of the following instead.

For example, the following are good candidates for using this method:

  • ALTER TABLE
  • CREATE or DROP table / trigger / view / index / virtual table
  • REINDEX
  • RELEASE
  • SAVEPOINT
  • PRAGMA that returns no data

When using enableWriteAheadLogging(), journal_mode is automatically managed by this class. So, do not set journal_mode using "PRAGMA journal_mode'" statement if your app is using enableWriteAheadLogging()

Note that PRAGMA values which apply on a per-connection basis should not be configured using this method; you should instead use execPerConnectionSQL(String, Object) to ensure that they are uniformly applied to all current and future connections.

Parameters
sql String: the SQL statement to be executed. Multiple statements separated by semicolons are not supported. This value cannot be null.

bindArgs Object: only byte[], String, Long and Double are supported in bindArgs. This value cannot be null.

Throws
SQLException if the SQL string is invalid

findEditTable

Added in API level 1
public static String findEditTable (String tables)

Finds the name of the first table, which is editable.

Parameters
tables String: a list of tables

Returns
String the first table listed

getAttachedDbs

Added in API level 11
public List<Pair<StringString>> getAttachedDbs ()

Returns list of full pathnames of all attached databases including the main database by executing 'pragma database_list' on the database.

Returns
List<Pair<StringString>> ArrayList of pairs of (database name, database file path) or null if the database is not open.

getLastChangedRowCount

Added in API level 35
public long getLastChangedRowCount ()

Return the number of database rows that were inserted, updated, or deleted by the most recent SQL statement within the current transaction.

Returns
long The number of rows changed by the most recent sql statement

Throws
IllegalStateException if there is no current transaction.

See also:

getLastInsertRowId

Added in API level 35
public long getLastInsertRowId ()

Return the "rowid" of the last row to be inserted on the current connection. This method must only be called when inside a transaction. IllegalStateException is thrown if the method is called outside a transaction. If the function is called before any inserts in the current transaction, the value returned will be from a previous transaction, which may be from a different thread. If no inserts have occurred on the current connection, the function returns 0. See the SQLite documentation for the specific details.

Returns
long The ROWID of the last row to be inserted under this connection.

Throws
IllegalStateException if there is no current transaction.

getMaximumSize

Added in API level 1
public long getMaximumSize ()

Returns the maximum size the database may grow to.

Returns
long the new maximum database size

getPageSize

Added in API level 1
public long getPageSize ()

Returns the current database page size, in bytes.

Returns
long the database page size, in bytes

getPath

Added in API level 1
public String getPath ()

Gets the path to the database file.

Returns
String The path to the database file.

getSyncedTables

Added in API level 1
Deprecated in API level 15
public Map<StringString> getSyncedTables ()

This method was deprecated in API level 15.
This method no longer serves any useful purpose and has been deprecated.

Deprecated.

Returns
Map<StringString>

getTotalChangedRowCount

Added in API level 35
public long getTotalChangedRowCount ()

Return the total number of database rows that have been inserted, updated, or deleted on the current connection since it was created. Due to Android's internal management of SQLite connections, the value may, or may not, include changes made in earlier transactions. Best practice is to compare values returned within a single transaction.

    database.beginTransaction();
    try {
        long initialValue = database.getTotalChangedRowCount();
        // Execute SQL statements
        long changedRows = database.getTotalChangedRowCount() - initialValue;
        // changedRows counts the total number of rows updated in the transaction.
    } finally {
        database.endTransaction();
    }
 

Returns
long The number of rows changed on the current connection.

Throws
IllegalStateException if there is no current transaction.

getVersion

Added in API level 1
public int getVersion ()

Gets the database version.

Returns
int the database version

inTransaction

Added in API level 1
public boolean inTransaction ()

Returns true if the current thread has a transaction pending.

Returns
boolean True if the current thread is in a transaction.

insert

Added in API level 1
public long insert (String table, 
                String nullColumnHack, 
                ContentValues values)

Convenience method for inserting a row into the database.

Parameters
table String: the table to insert the row into This value cannot be null.

nullColumnHack String: optional; may be null. SQL doesn't allow inserting a completely empty row without naming at least one column name. If your provided values is empty, no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your values is empty.

values ContentValues: this map contains the initial column values for the row. The keys should be the column names and the values the column values This value may be null.

Returns
long the row ID of the newly inserted row, or -1 if an error occurred

insertOrThrow

Added in API level 1
public long insertOrThrow (String table, 
                String nullColumnHack, 
                ContentValues values)

Convenience method for inserting a row into the database.

Parameters
table String: the table to insert the row into This value cannot be null.

nullColumnHack String: optional; may be null. SQL doesn't allow inserting a completely empty row without naming at least one column name. If your provided values is empty, no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your values is empty.

values ContentValues: this map contains the initial column values for the row. The keys should be the column names and the values the column values This value may be null.

Returns
long the row ID of the newly inserted row, or -1 if an error occurred

Throws
android.database.SQLException
SQLException

insertWithOnConflict

Added in API level 8
public long insertWithOnConflict (String table, 
                String nullColumnHack, 
                ContentValues initialValues, 
                int conflictAlgorithm)

General method for inserting a row into the database.

Parameters
table String: the table to insert the row into This value cannot be null.

nullColumnHack String: optional; may be null. SQL doesn't allow inserting a completely empty row without naming at least one column name. If your provided initialValues is empty, no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your initialValues is empty.

initialValues ContentValues: this map contains the initial column values for the row. The keys should be the column names and the values the column values This value may be null.

conflictAlgorithm int: for insert conflict resolver

Returns
long the row ID of the newly inserted row OR -1 if either the input parameter conflictAlgorithm = CONFLICT_IGNORE or an error occurred.

isDatabaseIntegrityOk

Added in API level 11
public boolean isDatabaseIntegrityOk ()

Runs 'pragma integrity_check' on the given database (and all the attached databases) and returns true if the given database (and all its attached databases) pass integrity_check, false otherwise.

If the result is false, then this method logs the errors reported by the integrity_check command execution.

Note that 'pragma integrity_check' on a database can take a long time.

Returns
boolean true if the given database (and all its attached databases) pass integrity_check, false otherwise.

isDbLockedByCurrentThread

Added in API level 1
public boolean isDbLockedByCurrentThread ()

Returns true if the current thread is holding an active connection to the database.

The name of this method comes from a time when having an active connection to the database meant that the thread was holding an actual lock on the database. Nowadays, there is no longer a true "database lock" although threads may block if they cannot acquire a database connection to perform a particular operation.

Returns
boolean True if the current thread is holding an active connection to the database.

isDbLockedByOtherThreads

Added in API level 1
Deprecated in API level 16
public boolean isDbLockedByOtherThreads ()

This method was deprecated in API level 16.
Always returns false. Do not use this method.

Always returns false.

There is no longer the concept of a database lock, so this method always returns false.

Returns
boolean False.

isOpen

Added in API level 1
public boolean isOpen ()

Returns true if the database is currently open.

Returns
boolean True if the database is currently open (has not been closed).

isReadOnly

Added in API level 1
public boolean isReadOnly ()

Returns true if the database is opened as read only.

Returns
boolean True if database is opened as read only.

isWriteAheadLoggingEnabled

Added in API level 16
public boolean isWriteAheadLoggingEnabled ()

Returns true if write-ahead logging has been enabled for this database.

Returns
boolean True if write-ahead logging has been enabled for this database.

markTableSyncable

Added in API level 1
Deprecated in API level 15
public void markTableSyncable (String table, 
                String deletedTable)

This method was deprecated in API level 15.
This method no longer serves any useful purpose and has been deprecated.

Mark this table as syncable. When an update occurs in this table the _sync_dirty field will be set to ensure proper syncing operation.

Parameters
table String: the table to mark as syncable

deletedTable String: The deleted table that corresponds to the syncable table

markTableSyncable

Added in API level 1
Deprecated in API level 15
public void markTableSyncable (String table, 
                String foreignKey, 
                String updateTable)

This method was deprecated in API level 15.
This method no longer serves any useful purpose and has been deprecated.

Mark this table as syncable, with the _sync_dirty residing in another table. When an update occurs in this table the _sync_dirty field of the row in updateTable with the _id in foreignKey will be set to ensure proper syncing operation.

Parameters
table String: an update on this table will trigger a sync time removal

foreignKey String: this is the column in table whose value is an _id in updateTable

updateTable String: this is the table that will have its _sync_dirty

needUpgrade

Added in API level 1
public boolean needUpgrade (int newVersion)

Returns true if the new version code is greater than the current database version.

Parameters
newVersion int: The new version code.

Returns
boolean True if the new version code is greater than the current database version.

openDatabase

Added in API level 1
public static SQLiteDatabase openDatabase (String path, 
                SQLiteDatabase.CursorFactory factory, 
                int flags)

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY and/or NO_LOCALIZED_COLLATORS.

Sets the locale of the database to the system's current locale. Call setLocale(Locale) if you would like something else.

Parameters
path String: to database file to open and/or create This value cannot be null.

factory SQLiteDatabase.CursorFactory: an optional factory class that is called to instantiate a cursor when query is called, or null for default

flags int: to control database access mode Value is either 0 or a combination of OPEN_READWRITE, OPEN_READONLY, CREATE_IF_NECESSARY, NO_LOCALIZED_COLLATORS, and ENABLE_WRITE_AHEAD_LOGGING

Returns
SQLiteDatabase the newly opened database

Throws
SQLiteException if the database cannot be opened

openDatabase

Added in API level 27
public static SQLiteDatabase openDatabase (File path, 
                SQLiteDatabase.OpenParams openParams)

Open the database according to the specified parameters

Parameters
path File: path to database file to open and/or create.

Important: The file should be constructed either from an absolute path or by using Context.getDatabasePath(String). This value cannot be null.

openParams SQLiteDatabase.OpenParams: configuration parameters that are used for opening SQLiteDatabase This value cannot be null.

Returns
SQLiteDatabase the newly opened database

Throws
SQLiteException if the database cannot be opened

openDatabase

Added in API level 11
public static SQLiteDatabase openDatabase (String path, 
                SQLiteDatabase.CursorFactory factory, 
                int flags, 
                DatabaseErrorHandler errorHandler)

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY and/or NO_LOCALIZED_COLLATORS.

Sets the locale of the database to the system's current locale. Call setLocale(Locale) if you would like something else.

Accepts input param: a concrete instance of DatabaseErrorHandler to be used to handle corruption when sqlite reports database corruption.

Parameters
path String: to database file to open and/or create This value cannot be null.

factory SQLiteDatabase.CursorFactory: an optional factory class that is called to instantiate a cursor when query is called, or null for default

flags int: to control database access mode Value is either 0 or a combination of OPEN_READWRITE, OPEN_READONLY, CREATE_IF_NECESSARY, NO_LOCALIZED_COLLATORS, and ENABLE_WRITE_AHEAD_LOGGING

errorHandler DatabaseErrorHandler: the DatabaseErrorHandler obj to be used to handle corruption when sqlite reports database corruption This value may be null.

Returns
SQLiteDatabase the newly opened database

Throws
SQLiteException if the database cannot be opened

openOrCreateDatabase

Added in API level 1
public static SQLiteDatabase openOrCreateDatabase (File file, 
                SQLiteDatabase.CursorFactory factory)

Equivalent to openDatabase(file.getPath(), factory, CREATE_IF_NECESSARY).

Parameters
file File: This value cannot be null.

factory SQLiteDatabase.CursorFactory: This value may be null.

Returns
SQLiteDatabase

openOrCreateDatabase

Added in API level 11
public static SQLiteDatabase openOrCreateDatabase (String path, 
                SQLiteDatabase.CursorFactory factory, 
                DatabaseErrorHandler errorHandler)

Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY, errorHandler).

Parameters
path String: This value cannot be null.

factory SQLiteDatabase.CursorFactory: This value may be null.

errorHandler DatabaseErrorHandler: This value may be null.

Returns
SQLiteDatabase

openOrCreateDatabase

Added in API level 1
public static SQLiteDatabase openOrCreateDatabase (String path, 
                SQLiteDatabase.CursorFactory factory)

Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY).

Parameters
path String: This value cannot be null.

factory SQLiteDatabase.CursorFactory: This value may be null.

Returns
SQLiteDatabase

query

Added in API level 1
public Cursor query (boolean distinct, 
                String table, 
                String[] columns, 
                String selection, 
                String[] selectionArgs, 
                String groupBy, 
                String having, 
                String orderBy, 
                String limit)

Query the given URL, returning a Cursor over the result set.

Parameters
distinct boolean: true if you want each row to be unique, false otherwise.

table String: The table name to compile the query against. This value cannot be null.

columns String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

groupBy String: A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having String: A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

limit String: Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

See also:

query

Added in API level 1
public Cursor query (String table, 
                String[] columns, 
                String selection, 
                String[] selectionArgs, 
                String groupBy, 
                String having, 
                String orderBy, 
                String limit)

Query the given table, returning a Cursor over the result set.

Parameters
table String: The table name to compile the query against. This value cannot be null.

columns String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

groupBy String: A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having String: A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

limit String: Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

See also:

query

Added in API level 16
public Cursor query (boolean distinct, 
                String table, 
                String[] columns, 
                String selection, 
                String[] selectionArgs, 
                String groupBy, 
                String having, 
                String orderBy, 
                String limit, 
                CancellationSignal cancellationSignal)

Query the given URL, returning a Cursor over the result set.

Parameters
distinct boolean: true if you want each row to be unique, false otherwise.

table String: The table name to compile the query against. This value cannot be null.

columns String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

groupBy String: A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having String: A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

limit String: Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

cancellationSignal CancellationSignal: A signal to cancel the operation in progress, or null if none. If the operation is canceled, then OperationCanceledException will be thrown when the query is executed.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

See also:

query

Added in API level 1
public Cursor query (String table, 
                String[] columns, 
                String selection, 
                String[] selectionArgs, 
                String groupBy, 
                String having, 
                String orderBy)

Query the given table, returning a Cursor over the result set.

Parameters
table String: The table name to compile the query against. This value cannot be null.

columns String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

groupBy String: A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having String: A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

See also:

queryWithFactory

Added in API level 16
public Cursor queryWithFactory (SQLiteDatabase.CursorFactory cursorFactory, 
                boolean distinct, 
                String table, 
                String[] columns, 
                String selection, 
                String[] selectionArgs, 
                String groupBy, 
                String having, 
                String orderBy, 
                String limit, 
                CancellationSignal cancellationSignal)

Query the given URL, returning a Cursor over the result set.

Parameters
cursorFactory SQLiteDatabase.CursorFactory: the cursor factory to use, or null for the default factory

distinct boolean: true if you want each row to be unique, false otherwise.

table String: The table name to compile the query against. This value cannot be null.

columns String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

groupBy String: A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having String: A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

limit String: Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

cancellationSignal CancellationSignal: A signal to cancel the operation in progress, or null if none. If the operation is canceled, then OperationCanceledException will be thrown when the query is executed.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

See also:

queryWithFactory

Added in API level 1
public Cursor queryWithFactory (SQLiteDatabase.CursorFactory cursorFactory, 
                boolean distinct, 
                String table, 
                String[] columns, 
                String selection, 
                String[] selectionArgs, 
                String groupBy, 
                String having, 
                String orderBy, 
                String limit)

Query the given URL, returning a Cursor over the result set.

Parameters
cursorFactory SQLiteDatabase.CursorFactory: the cursor factory to use, or null for the default factory

distinct boolean: true if you want each row to be unique, false otherwise.

table String: The table name to compile the query against. This value cannot be null.

columns String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.

selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.

selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

groupBy String: A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.

having String: A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.

orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

limit String: Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

See also:

rawQuery

Added in API level 16
public Cursor rawQuery (String sql, 
                String[] selectionArgs, 
                CancellationSignal cancellationSignal)

Runs the provided SQL and returns a Cursor over the result set.

Parameters
sql String: the SQL query. The SQL string must not be ; terminated This value cannot be null.

selectionArgs String: You may include ?s in where clause in the query, which will be replaced by the values from selectionArgs. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

cancellationSignal CancellationSignal: A signal to cancel the operation in progress, or null if none. If the operation is canceled, then OperationCanceledException will be thrown when the query is executed.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

rawQuery

Added in API level 1
public Cursor rawQuery (String sql, 
                String[] selectionArgs)

Runs the provided SQL and returns a Cursor over the result set.

Parameters
sql String: the SQL query. The SQL string must not be ; terminated This value cannot be null.

selectionArgs String: You may include ?s in where clause in the query, which will be replaced by the values from selectionArgs. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

rawQueryWithFactory

Added in API level 16
public Cursor rawQueryWithFactory (SQLiteDatabase.CursorFactory cursorFactory, 
                String sql, 
                String[] selectionArgs, 
                String editTable, 
                CancellationSignal cancellationSignal)

Runs the provided SQL and returns a cursor over the result set.

Parameters
cursorFactory SQLiteDatabase.CursorFactory: the cursor factory to use, or null for the default factory

sql String: the SQL query. The SQL string must not be ; terminated This value cannot be null.

selectionArgs String: You may include ?s in where clause in the query, which will be replaced by the values from selectionArgs. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

editTable String: the name of the first table, which is editable This value cannot be null.

cancellationSignal CancellationSignal: A signal to cancel the operation in progress, or null if none. If the operation is canceled, then OperationCanceledException will be thrown when the query is executed.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

rawQueryWithFactory

Added in API level 1
public Cursor rawQueryWithFactory (SQLiteDatabase.CursorFactory cursorFactory, 
                String sql, 
                String[] selectionArgs, 
                String editTable)

Runs the provided SQL and returns a cursor over the result set.

Parameters
cursorFactory SQLiteDatabase.CursorFactory: the cursor factory to use, or null for the default factory

sql String: the SQL query. The SQL string must not be ; terminated This value cannot be null.

selectionArgs String: You may include ?s in where clause in the query, which will be replaced by the values from selectionArgs. The values will be bound as Strings. If selection is null or does not contain ?s then selectionArgs may be null.

editTable String: the name of the first table, which is editable This value cannot be null.

Returns
Cursor A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details. This value cannot be null.

releaseMemory

Added in API level 1
public static int releaseMemory ()

Attempts to release memory that SQLite holds but does not require to operate properly. Typically this memory will come from the page cache.

Returns
int the number of bytes actually released

replace

Added in API level 1
public long replace (String table, 
                String nullColumnHack, 
                ContentValues initialValues)

Convenience method for replacing a row in the database. Inserts a new row if a row does not already exist.

Parameters
table String: the table in which to replace the row This value cannot be null.

nullColumnHack String: optional; may be null. SQL doesn't allow inserting a completely empty row without naming at least one column name. If your provided initialValues is empty, no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your initialValues is empty.

initialValues ContentValues: this map contains the initial column values for the row. The keys should be the column names and the values the column values. This value may be null.

Returns
long the row ID of the newly inserted row, or -1 if an error occurred

replaceOrThrow

Added in API level 1
public long replaceOrThrow (String table, 
                String nullColumnHack, 
                ContentValues initialValues)

Convenience method for replacing a row in the database. Inserts a new row if a row does not already exist.

Parameters
table String: the table in which to replace the row This value cannot be null.

nullColumnHack String: optional; may be null. SQL doesn't allow inserting a completely empty row without naming at least one column name. If your provided initialValues is empty, no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your initialValues is empty.

initialValues ContentValues: this map contains the initial column values for the row. The keys should be the column names and the values the column values. This value may be null.

Returns
long the row ID of the newly inserted row, or -1 if an error occurred

Throws
android.database.SQLException
SQLException

setCustomAggregateFunction

Added in API level 30
public void setCustomAggregateFunction (String functionName, 
                BinaryOperator<String> aggregateFunction)

Register a custom aggregate function that can be called from SQL expressions.

For example, registering a custom aggregation function named LONGEST could be used in a query like SELECT LONGEST(name) FROM employees.

The implementation of this method follows the reduction flow outlined in Stream.reduce(BinaryOperator), and the custom aggregation function is expected to be an associative accumulation function, as defined by that class.

When attempting to register multiple functions with the same function name, SQLite will replace any previously defined functions with the latest definition, regardless of what function type they are. SQLite does not support unregistering functions.

Parameters
functionName String: Case-insensitive name to register this function under, limited to 255 UTF-8 bytes in length. This value cannot be null.

aggregateFunction BinaryOperator: Functional interface that will be invoked when the function name is used by a SQL statement. The argument values from the SQL statement are passed to the functional interface, and the return values from the functional interface are returned back into the SQL statement. This value cannot be null.

Throws
SQLiteException if the custom function could not be registered.

setCustomScalarFunction

Added in API level 30
public void setCustomScalarFunction (String functionName, 
                UnaryOperator<String> scalarFunction)

Register a custom scalar function that can be called from SQL expressions.

For example, registering a custom scalar function named REVERSE could be used in a query like SELECT REVERSE(name) FROM employees.

When attempting to register multiple functions with the same function name, SQLite will replace any previously defined functions with the latest definition, regardless of what function type they are. SQLite does not support unregistering functions.

Parameters
functionName String: Case-insensitive name to register this function under, limited to 255 UTF-8 bytes in length. This value cannot be null.

scalarFunction UnaryOperator: Functional interface that will be invoked when the function name is used by a SQL statement. The argument values from the SQL statement are passed to the functional interface, and the return values from the functional interface are returned back into the SQL statement. This value cannot be null.

Throws
SQLiteException if the custom function could not be registered.

setForeignKeyConstraintsEnabled

Added in API level 16
public void setForeignKeyConstraintsEnabled (boolean enable)

Sets whether foreign key constraints are enabled for the database.

By default, foreign key constraints are not enforced by the database. This method allows an application to enable foreign key constraints. It must be called each time the database is opened to ensure that foreign key constraints are enabled for the session.

A good time to call this method is right after calling openOrCreateDatabase(File, CursorFactory) or in the SQLiteOpenHelper#onConfigure callback.

When foreign key constraints are disabled, the database does not check whether changes to the database will violate foreign key constraints. Likewise, when foreign key constraints are disabled, the database will not execute cascade delete or update triggers. As a result, it is possible for the database state to become inconsistent. To perform a database integrity check, call isDatabaseIntegrityOk().

This method must not be called while a transaction is in progress.

See also SQLite Foreign Key Constraints for more details about foreign key constraint support.

Parameters
enable boolean: True to enable foreign key constraints, false to disable them.

Throws
IllegalStateException if the are transactions is in progress when this method is called.

setLocale

Added in API level 1
public void setLocale (Locale locale)

Sets the locale for this database. Does nothing if this database has the NO_LOCALIZED_COLLATORS flag set or was opened read only.

Parameters
locale Locale: The new locale.

Throws
SQLException if the locale could not be set. The most common reason for this is that there is no collator available for the locale you requested. In this case the database remains unchanged.

setLockingEnabled

Added in API level 1
Deprecated in API level 16
public void setLockingEnabled (boolean lockingEnabled)

This method was deprecated in API level 16.
This method now does nothing. Do not use.

Control whether or not the SQLiteDatabase is made thread-safe by using locks around critical sections. This is pretty expensive, so if you know that your DB will only be used by a single thread then you should set this to false. The default is true.

Parameters
lockingEnabled boolean: set to true to enable locks, false otherwise

setMaxSqlCacheSize

Added in API level 11
public void setMaxSqlCacheSize (int cacheSize)

Sets the maximum size of the prepared-statement cache for this database. (size of the cache = number of compiled-sql-statements stored in the cache).

Maximum cache size can ONLY be increased from its current size (default = 10). If this method is called with smaller size than the current maximum value, then IllegalStateException is thrown.

This method is thread-safe.

Parameters
cacheSize int: the size of the cache. can be (0 to MAX_SQL_CACHE_SIZE)

Throws
IllegalStateException if input cacheSize > MAX_SQL_CACHE_SIZE.

setMaximumSize

Added in API level 1
public long setMaximumSize (long numBytes)

Sets the maximum size the database will grow to. The maximum size cannot be set below the current size.

Parameters
numBytes long: the maximum database size, in bytes

Returns
long the new maximum database size

setPageSize

Added in API level 1
public void setPageSize (long numBytes)

Sets the database page size. The page size must be a power of two. This method does not work if any data has been written to the database file, and must be called right after the database has been created.

Parameters
numBytes long: the database page size, in bytes

setTransactionSuccessful

Added in API level 1
public void setTransactionSuccessful ()

Marks the current transaction as successful. Do not do any more database work between calling this and calling endTransaction. Do as little non-database work as possible in that situation too. If any errors are encountered between this and endTransaction the transaction will still be committed.

Throws
IllegalStateException if the current thread is not in a transaction or the transaction is already marked as successful.

setVersion

Added in API level 1
public void setVersion (int version)

Sets the database version.

Parameters
version int: the new database version

toString

Added in API level 1
public String toString ()

Returns a string representation of the object.

Returns
String a string representation of the object.

update

Added in API level 1
public int update (String table, 
                ContentValues values, 
                String whereClause, 
                String[] whereArgs)

Convenience method for updating rows in the database.

Parameters
table String: the table to update in This value cannot be null.

values ContentValues: a map from column names to new column values. null is a valid value that will be translated to NULL.

whereClause String: the optional WHERE clause to apply when updating. Passing null will update all rows.

whereArgs String: You may include ?s in the where clause, which will be replaced by the values from whereArgs. The values will be bound as Strings. If whereClause is null or does not contain ?s then whereArgs may be null.

Returns
int the number of rows affected

updateWithOnConflict

Added in API level 8
public int updateWithOnConflict (String table, 
                ContentValues values, 
                String whereClause, 
                String[] whereArgs, 
                int conflictAlgorithm)

Convenience method for updating rows in the database.

Parameters
table String: the table to update in This value cannot be null.

values ContentValues: a map from column names to new column values. null is a valid value that will be translated to NULL.

whereClause String: the optional WHERE clause to apply when updating. Passing null will update all rows.

whereArgs String: You may include ?s in the where clause, which will be replaced by the values from whereArgs. The values will be bound as Strings. If whereClause is null or does not contain ?s then whereArgs may be null.

conflictAlgorithm int: for update conflict resolver

Returns
int the number of rows affected

validateSql

Added in API level 24
public void validateSql (String sql, 
                CancellationSignal cancellationSignal)

Verifies that a SQL SELECT statement is valid by compiling it. If the SQL statement is not valid, this method will throw a SQLiteException.

Parameters
sql String: SQL to be validated This value cannot be null.

cancellationSignal CancellationSignal: A signal to cancel the operation in progress, or null if none. If the operation is canceled, then OperationCanceledException will be thrown when the query is executed.

Throws
SQLiteException if sql is invalid

yieldIfContended

Added in API level 1
Deprecated in API level 15
public boolean yieldIfContended ()

This method was deprecated in API level 15.
if the db is locked more than once (because of nested transactions) then the lock will not be yielded. Use yieldIfContendedSafely instead.

Temporarily end the transaction to let other threads run. The transaction is assumed to be successful so far. Do not call setTransactionSuccessful before calling this. When this returns a new transaction will have been created but not marked as successful.

Returns
boolean true if the transaction was yielded

yieldIfContendedSafely

Added in API level 3
public boolean yieldIfContendedSafely ()

Temporarily end the transaction to let other threads run. The transaction is assumed to be successful so far. Do not call setTransactionSuccessful before calling this. When this returns a new transaction will have been created but not marked as successful. This assumes that there are no nested transactions (beginTransaction has only been called once) and will throw an exception if that is not the case.

Returns
boolean true if the transaction was yielded

yieldIfContendedSafely

Added in API level 5
public boolean yieldIfContendedSafely (long sleepAfterYieldDelay)

Temporarily end the transaction to let other threads run. The transaction is assumed to be successful so far. Do not call setTransactionSuccessful before calling this. When this returns a new transaction will have been created but not marked as successful. This assumes that there are no nested transactions (beginTransaction has only been called once) and will throw an exception if that is not the case.

Parameters
sleepAfterYieldDelay long: if > 0, sleep this long before starting a new transaction if the lock was actually yielded. This will allow other background threads to make some more progress than they would if we started the transaction immediately.

Returns
boolean true if the transaction was yielded

Protected methods

finalize

Added in API level 1
protected void finalize ()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. A subclass overrides the finalize method to dispose of system resources or to perform other cleanup.

The general contract of finalize is that it is invoked if and when the Java virtual machine has determined that there is no longer any means by which this object can be accessed by any thread that has not yet died, except as a result of an action taken by the finalization of some other object or class which is ready to be finalized. The finalize method may take any action, including making this object available again to other threads; the usual purpose of finalize, however, is to perform cleanup actions before the object is irrevocably discarded. For example, the finalize method for an object that represents an input/output connection might perform explicit I/O transactions to break the connection before the object is permanently discarded.

The finalize method of class Object performs no special action; it simply returns normally. Subclasses of Object may override this definition.

The Java programming language does not guarantee which thread will invoke the finalize method for any given object. It is guaranteed, however, that the thread that invokes finalize will not be holding any user-visible synchronization locks when finalize is invoked. If an uncaught exception is thrown by the finalize method, the exception is ignored and finalization of that object terminates.

After the finalize method has been invoked for an object, no further action is taken until the Java virtual machine has again determined that there is no longer any means by which this object can be accessed by any thread that has not yet died, including possible actions by other objects or classes which are ready to be finalized, at which point the object may be discarded.

The finalize method is never invoked more than once by a Java virtual machine for any given object.

Any exception thrown by the finalize method causes the finalization of this object to be halted, but is otherwise ignored.

Throws
Throwable

onAllReferencesReleased

Added in API level 1
protected void onAllReferencesReleased ()

Called when the last reference to the object was released by a call to releaseReference() or close().