com.couchbase.lite.internal.database.sqlite

Class SQLiteDatabase

java.lang.Object

com.couchbase.lite.internal.database.sqlite.SQLiteClosable

com.couchbase.lite.internal.database.sqlite.SQLiteDatabase

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public final class SQLiteDatabase
extends SQLiteClosable

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.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	SQLiteDatabase.CursorFactory Used to allow returning sub-classes of Cursor when calling query.
static interface	SQLiteDatabase.CustomFunction A callback interface for a custom sqlite3 function.

Field Summary

Fields

Modifier and Type	Field and Description
static int	CONFLICT_ABORT When a constraint violation occurs,no ROLLBACK is executed so changes from prior commands within the same transaction are preserved.
static int	CONFLICT_FAIL When a constraint violation occurs, the command aborts with a return code SQLITE_CONSTRAINT.
static int	CONFLICT_IGNORE When a constraint violation occurs, the one row that contains the constraint violation is not inserted or changed.
static int	CONFLICT_NONE Use the following when no conflict action is specified.
static 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.
static 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.
static int	CREATE_IF_NECESSARY Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) to create the database file if it does not already exist.
static int	ENABLE_WRITE_AHEAD_LOGGING Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) to open the database file with write-ahead logging enabled by default.
static int	MAX_SQL_CACHE_SIZE Absolute max value that can be set by setMaxSqlCacheSize(int).
static int	OPEN_READ_MASK
static int	OPEN_READONLY Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) to open the database for reading only.
static int	OPEN_READWRITE Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) to open the database for reading and writing.
static 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.

Method Summary

Modifier and Type	Method and Description
void	beginTransaction() Begins a transaction in EXCLUSIVE mode.
void	beginTransactionNonExclusive() Begins a transaction in IMMEDIATE mode.
void	beginTransactionWithListener(SQLiteTransactionListener transactionListener) Begins a transaction in EXCLUSIVE mode.
void	beginTransactionWithListenerNonExclusive(SQLiteTransactionListener transactionListener) Begins a transaction in IMMEDIATE mode.
SQLiteStatement	compileStatement(java.lang.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.
int	delete(java.lang.String table, java.lang.String whereClause, java.lang.String[] whereArgs) Convenience method for deleting rows in the database.
static boolean	deleteDatabase(java.io.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	execSQL(java.lang.String sql) Execute a single SQL statement that is NOT a SELECT or any other SQL statement that returns data.
void	execSQL(java.lang.String sql, java.lang.Object[] bindArgs) Execute a single SQL statement that is NOT a SELECT/INSERT/UPDATE/DELETE.
protected void	finalize()
static java.lang.String	findEditTable(java.lang.String tables) Finds the name of the first table, which is editable.
java.util.List<Pair<java.lang.String,java.lang.String>>	getAttachedDbs() Returns list of full pathnames of all attached databases including the main database by executing 'pragma database_list' on the database.
long	getMaximumSize() Returns the maximum size the database may grow to.
long	getPageSize() Returns the current database page size, in bytes.
java.lang.String	getPath() Gets the path to the database file.
int	getVersion() Gets the database version.
long	insert(java.lang.String table, java.lang.String nullColumnHack, ContentValues values) Convenience method for inserting a row into the database.
long	insertOrThrow(java.lang.String table, java.lang.String nullColumnHack, ContentValues values) Convenience method for inserting a row into the database.
long	insertWithOnConflict(java.lang.String table, java.lang.String nullColumnHack, ContentValues initialValues, int conflictAlgorithm) General method for inserting a row into the database.
boolean	inTransaction() Returns true if the current thread has a transaction pending.
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() Deprecated. Always returns false. Do not use this method.
boolean	isInMemoryDatabase() Returns true if the database is in-memory db.
boolean	isOpen() Returns true if the database is currently open.
boolean	isReadOnly() Returns true if the database is opened as read only.
static boolean	isSupportEncryption()
boolean	isWriteAheadLoggingEnabled() Returns true if write-ahead logging has been enabled for this database.
void	markTableSyncable(java.lang.String table, java.lang.String deletedTable) Deprecated. This method no longer serves any useful purpose and has been deprecated.
void	markTableSyncable(java.lang.String table, java.lang.String foreignKey, java.lang.String updateTable) Deprecated. 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.
protected void	onAllReferencesReleased() Called when the last reference to the object was released by a call to SQLiteClosable.releaseReference() or SQLiteClosable.close().
static SQLiteDatabase	openDatabase(java.lang.String path, SQLiteDatabase.CursorFactory factory, int flags) Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY.
static SQLiteDatabase	openDatabase(java.lang.String path, SQLiteDatabase.CursorFactory factory, int flags, DatabaseErrorHandler errorHandler) Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY.
static SQLiteDatabase	openDatabase(java.lang.String path, SQLiteDatabase.CursorFactory factory, int flags, int walConnectionPoolSize, DatabaseErrorHandler errorHandler, SQLiteConnectionListener connectionListener) Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY.
static SQLiteDatabase	openOrCreateDatabase(java.io.File file, SQLiteDatabase.CursorFactory factory) Equivalent to openDatabase(file.getPath(), factory, CREATE_IF_NECESSARY).
static SQLiteDatabase	openOrCreateDatabase(java.lang.String path, SQLiteDatabase.CursorFactory factory) Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY).
static SQLiteDatabase	openOrCreateDatabase(java.lang.String path, SQLiteDatabase.CursorFactory factory, DatabaseErrorHandler errorHandler) Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY, errorHandler).
Cursor	query(boolean distinct, java.lang.String table, java.lang.String[] columns, java.lang.String selection, java.lang.String[] selectionArgs, java.lang.String groupBy, java.lang.String having, java.lang.String orderBy, java.lang.String limit) Query the given URL, returning a Cursor over the result set.
Cursor	query(boolean distinct, java.lang.String table, java.lang.String[] columns, java.lang.String selection, java.lang.String[] selectionArgs, java.lang.String groupBy, java.lang.String having, java.lang.String orderBy, java.lang.String limit, CancellationSignal cancellationSignal) Query the given URL, returning a Cursor over the result set.
Cursor	query(java.lang.String table, java.lang.String[] columns, java.lang.String selection, java.lang.String[] selectionArgs, java.lang.String groupBy, java.lang.String having, java.lang.String orderBy) Query the given table, returning a Cursor over the result set.
Cursor	query(java.lang.String table, java.lang.String[] columns, java.lang.String selection, java.lang.String[] selectionArgs, java.lang.String groupBy, java.lang.String having, java.lang.String orderBy, java.lang.String limit) Query the given table, returning a Cursor over the result set.
Cursor	queryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, boolean distinct, java.lang.String table, java.lang.String[] columns, java.lang.String selection, java.lang.String[] selectionArgs, java.lang.String groupBy, java.lang.String having, java.lang.String orderBy, java.lang.String limit) Query the given URL, returning a Cursor over the result set.
Cursor	queryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, boolean distinct, java.lang.String table, java.lang.String[] columns, java.lang.String selection, java.lang.String[] selectionArgs, java.lang.String groupBy, java.lang.String having, java.lang.String orderBy, java.lang.String limit, CancellationSignal cancellationSignal) Query the given URL, returning a Cursor over the result set.
Cursor	rawQuery(java.lang.String sql, java.lang.String[] selectionArgs) Runs the provided SQL and returns a Cursor over the result set.
Cursor	rawQuery(java.lang.String sql, java.lang.String[] selectionArgs, CancellationSignal cancellationSignal) Runs the provided SQL and returns a Cursor over the result set.
Cursor	rawQueryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, java.lang.String sql, java.lang.String[] selectionArgs, java.lang.String editTable) Runs the provided SQL and returns a cursor over the result set.
Cursor	rawQueryWithFactory(SQLiteDatabase.CursorFactory cursorFactory, java.lang.String sql, java.lang.String[] selectionArgs, java.lang.String editTable, CancellationSignal cancellationSignal) Runs the provided SQL and returns a cursor over the result set.
void	reopenReadWrite() Reopens the database in read-write mode.
long	replace(java.lang.String table, java.lang.String nullColumnHack, ContentValues initialValues) Convenience method for replacing a row in the database.
long	replaceOrThrow(java.lang.String table, java.lang.String nullColumnHack, ContentValues initialValues) Convenience method for replacing a row in the database.
static void	setDatabasePlatformSupport(DatabasePlatformSupport supporter) Set an optional platform support object.
void	setForeignKeyConstraintsEnabled(boolean enable) Sets whether foreign key constraints are enabled for the database.
void	setLocale(java.util.Locale locale) Sets the locale for this database.
void	setLockingEnabled(boolean lockingEnabled) Deprecated. This method now does nothing. Do not use.
long	setMaximumSize(long numBytes) Sets the maximum size the database will grow to.
void	setMaxSqlCacheSize(int cacheSize) Sets the maximum size of the prepared-statement cache for this database.
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.
java.lang.String	toString()
int	update(java.lang.String table, ContentValues values, java.lang.String whereClause, java.lang.String[] whereArgs) Convenience method for updating rows in the database.
int	updateWithOnConflict(java.lang.String table, ContentValues values, java.lang.String whereClause, java.lang.String[] whereArgs, int conflictAlgorithm) Convenience method for updating rows in the database.
boolean	yieldIfContended() Deprecated. if the db is locked more than once (becuase 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.

Methods inherited from class com.couchbase.lite.internal.database.sqlite.SQLiteClosable

acquireReference, close, onAllReferencesReleasedFromContainer, releaseReference, releaseReferenceFromContainer

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

CONFLICT_ROLLBACK

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.

See Also:

Constant Field Values

CONFLICT_ABORT

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.

See Also:

Constant Field Values

CONFLICT_FAIL

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.

See Also:

Constant Field Values

CONFLICT_IGNORE

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.

See Also:

Constant Field Values

CONFLICT_REPLACE

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.

See Also:

Constant Field Values

CONFLICT_NONE

public static final int CONFLICT_NONE

Use the following when no conflict action is specified.

See Also:

Constant Field Values

SQLITE_MAX_LIKE_PATTERN_LENGTH

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, paranoid 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.

See Also:

Constant Field Values

OPEN_READWRITE

public static final int OPEN_READWRITE

Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) 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.

See Also:

Constant Field Values

OPEN_READONLY

public static final int OPEN_READONLY

Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) to open the database for reading only. This is the only reliable way to open a database if the disk may be full.

See Also:

Constant Field Values

OPEN_READ_MASK

public static final int OPEN_READ_MASK

See Also:

Constant Field Values

CREATE_IF_NECESSARY

public static final int CREATE_IF_NECESSARY

Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) to create the database file if it does not already exist.

See Also:

Constant Field Values

ENABLE_WRITE_AHEAD_LOGGING

public static final int ENABLE_WRITE_AHEAD_LOGGING

Open flag: Flag for openDatabase(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int) 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.

See Also:

enableWriteAheadLogging(), Constant Field Values

MAX_SQL_CACHE_SIZE

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.

See Also:

Constant Field Values

Method Detail

finalize

protected void finalize()
                 throws java.lang.Throwable

Overrides:

finalize in class java.lang.Object

Throws:

java.lang.Throwable

onAllReferencesReleased

protected void onAllReferencesReleased()

Description copied from class: SQLiteClosable

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

Specified by:

onAllReferencesReleased in class SQLiteClosable

setLockingEnabled

@Deprecated
public void setLockingEnabled(boolean lockingEnabled)

Deprecated. 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 - set to true to enable locks, false otherwise

isSupportEncryption

public static boolean isSupportEncryption()

beginTransaction

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

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();
   }
 

beginTransactionWithListener

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 - listener that should be notified when the transaction begins, commits, or is rolled back, either explicitly or by a call to yieldIfContendedSafely().

beginTransactionWithListenerNonExclusive

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 - listener that should be notified when the transaction begins, commits, or is rolled back, either explicitly or by a call to yieldIfContendedSafely().

endTransaction

public void endTransaction()

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

setTransactionSuccessful

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:

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

inTransaction

public boolean inTransaction()

Returns true if the current thread has a transaction pending.

Returns:

True if the current thread is in a transaction.

isDbLockedByCurrentThread

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:

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

isDbLockedByOtherThreads

@Deprecated
public boolean isDbLockedByOtherThreads()

Deprecated. 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:

False.

yieldIfContended

@Deprecated
public boolean yieldIfContended()

Deprecated. if the db is locked more than once (becuase 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:

true if the transaction was yielded

yieldIfContendedSafely

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:

true if the transaction was yielded

yieldIfContendedSafely

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 - 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:

true if the transaction was yielded

openDatabase

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

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY.

Parameters:

path - to database file to open and/or create

factory - an optional factory class that is called to instantiate a cursor when query is called, or null for default

flags - to control database access mode

Returns:

the newly opened database

Throws:

SQLiteException - if the database cannot be opened

openDatabase

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

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY.

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

Parameters:

path - to database file to open and/or create

factory - an optional factory class that is called to instantiate a cursor when query is called, or null for default

flags - to control database access mode

errorHandler - the DatabaseErrorHandler obj to be used to handle corruption when sqlite reports database corruption

Returns:

the newly opened database

Throws:

SQLiteException - if the database cannot be opened

openDatabase

public static SQLiteDatabase openDatabase(java.lang.String path,
                                          SQLiteDatabase.CursorFactory factory,
                                          int flags,
                                          int walConnectionPoolSize,
                                          DatabaseErrorHandler errorHandler,
                                          SQLiteConnectionListener connectionListener)

Open the database according to the flags OPEN_READWRITE OPEN_READONLY CREATE_IF_NECESSARY.

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

Parameters:

path - to database file to open and/or create

factory - an optional factory class that is called to instantiate a cursor when query is called, or null for default

flags - to control database access mode

walConnectionPoolSize - maximum connection pool size

errorHandler - the DatabaseErrorHandler obj to be used to handle corruption when sqlite reports database corruption

Returns:

the newly opened database

Throws:

SQLiteException - if the database cannot be opened

openOrCreateDatabase

public static SQLiteDatabase openOrCreateDatabase(java.io.File file,
                                                  SQLiteDatabase.CursorFactory factory)

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

openOrCreateDatabase

public static SQLiteDatabase openOrCreateDatabase(java.lang.String path,
                                                  SQLiteDatabase.CursorFactory factory)

Equivalent to openDatabase(path, factory, CREATE_IF_NECESSARY).

openOrCreateDatabase

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

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

setDatabasePlatformSupport

public static void setDatabasePlatformSupport(DatabasePlatformSupport supporter)

Set an optional platform support object. This helps SQLiteDatabase optimizing some of their operations.

Parameters:

supporter - platform support object

deleteDatabase

public static boolean deleteDatabase(java.io.File file)

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

Parameters:

file - The database file path.

Returns:

True if the database was successfully deleted.

reopenReadWrite

public void reopenReadWrite()

Reopens the database in read-write mode. If the database is already read-write, does nothing.

Throws:

SQLiteException - if the database could not be reopened as requested, in which case it remains open in read only mode.

java.lang.IllegalStateException - if the database is not open.

See Also:

isReadOnly()

create

public static SQLiteDatabase create(SQLiteDatabase.CursorFactory factory)

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

Parameters:

factory - an optional factory class that is called to instantiate a cursor when query is called

Returns:

a SQLiteDatabase object, or null if the database can't be created

getVersion

public int getVersion()

Gets the database version.

Returns:

the database version

setVersion

public void setVersion(int version)

Sets the database version.

Parameters:

version - the new database version

getMaximumSize

public long getMaximumSize()

Returns the maximum size the database may grow to.

Returns:

the new maximum database size

setMaximumSize

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 - the maximum database size, in bytes

Returns:

the new maximum database size

getPageSize

public long getPageSize()

Returns the current database page size, in bytes.

Returns:

the database page size, in bytes

setPageSize

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 - the database page size, in bytes

markTableSyncable

@Deprecated
public void markTableSyncable(java.lang.String table,
                                          java.lang.String deletedTable)

Deprecated. 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 - the table to mark as syncable

deletedTable - The deleted table that corresponds to the syncable table

markTableSyncable

@Deprecated
public void markTableSyncable(java.lang.String table,
                                          java.lang.String foreignKey,
                                          java.lang.String updateTable)

Deprecated. 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 - an update on this table will trigger a sync time removal

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

updateTable - this is the table that will have its _sync_dirty

findEditTable

public static java.lang.String findEditTable(java.lang.String tables)

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

Parameters:

tables - a list of tables

Returns:

the first table listed

compileStatement

public SQLiteStatement compileStatement(java.lang.String sql)
                                 throws SQLException

Compiles an SQL statement into a reusable pre-compiled statement object. The parameters are identical to execSQL(String). You may put ?s in the statement and fill in those values with SQLiteProgram.bindString(int, java.lang.String) and SQLiteProgram.bindLong(int, long) 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 - The raw SQL statement, may contain ? for unknown values to be bound later.

Returns:

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

Throws:

SQLException

query

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

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

Parameters:

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

table - The table name to compile the query against.

columns - 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 - 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 - You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy - 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 - 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 - 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 - Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

Returns:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

See Also:

Cursor

query

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

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

Parameters:

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

table - The table name to compile the query against.

columns - 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 - 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 - You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy - 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 - 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 - 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 - Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

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:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

See Also:

Cursor

queryWithFactory

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

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

Parameters:

cursorFactory - the cursor factory to use, or null for the default factory

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

table - The table name to compile the query against.

columns - 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 - 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 - You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy - 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 - 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 - 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 - Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

Returns:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

See Also:

Cursor

queryWithFactory

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

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

Parameters:

cursorFactory - the cursor factory to use, or null for the default factory

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

table - The table name to compile the query against.

columns - 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 - 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 - You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy - 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 - 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 - 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 - Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

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:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

See Also:

Cursor

query

public Cursor query(java.lang.String table,
                    java.lang.String[] columns,
                    java.lang.String selection,
                    java.lang.String[] selectionArgs,
                    java.lang.String groupBy,
                    java.lang.String having,
                    java.lang.String orderBy)

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

Parameters:

table - The table name to compile the query against.

columns - 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 - 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 - You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy - 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 - 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 - 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:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

See Also:

Cursor

query

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

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

Parameters:

table - The table name to compile the query against.

columns - 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 - 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 - You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.

groupBy - 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 - 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 - 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 - Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.

Returns:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

See Also:

Cursor

rawQuery

public Cursor rawQuery(java.lang.String sql,
                       java.lang.String[] selectionArgs)

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

Parameters:

sql - the SQL query. The SQL string must not be ; terminated

selectionArgs - 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.

Returns:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

rawQuery

public Cursor rawQuery(java.lang.String sql,
                       java.lang.String[] selectionArgs,
                       CancellationSignal cancellationSignal)

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

Parameters:

sql - the SQL query. The SQL string must not be ; terminated

selectionArgs - 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.

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:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

rawQueryWithFactory

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

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

Parameters:

cursorFactory - the cursor factory to use, or null for the default factory

sql - the SQL query. The SQL string must not be ; terminated

selectionArgs - 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.

editTable - the name of the first table, which is editable

Returns:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

rawQueryWithFactory

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

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

Parameters:

cursorFactory - the cursor factory to use, or null for the default factory

sql - the SQL query. The SQL string must not be ; terminated

selectionArgs - 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.

editTable - the name of the first table, which is editable

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:

A Cursor object, which is positioned before the first entry. Note that Cursors are not synchronized, see the documentation for more details.

insert

public long insert(java.lang.String table,
                   java.lang.String nullColumnHack,
                   ContentValues values)

Convenience method for inserting a row into the database.

Parameters:

table - the table to insert the row into

nullColumnHack - 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 - this map contains the initial column values for the row. The keys should be the column names and the values the column values

Returns:

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

insertOrThrow

public long insertOrThrow(java.lang.String table,
                          java.lang.String nullColumnHack,
                          ContentValues values)
                   throws SQLException

Convenience method for inserting a row into the database.

Parameters:

table - the table to insert the row into

nullColumnHack - 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 - this map contains the initial column values for the row. The keys should be the column names and the values the column values

Returns:

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

Throws:

SQLException

replace

public long replace(java.lang.String table,
                    java.lang.String nullColumnHack,
                    ContentValues initialValues)

Convenience method for replacing a row in the database.

Parameters:

table - the table in which to replace the row

nullColumnHack - 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 - this map contains the initial column values for the row.

Returns:

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

replaceOrThrow

public long replaceOrThrow(java.lang.String table,
                           java.lang.String nullColumnHack,
                           ContentValues initialValues)
                    throws SQLException

Convenience method for replacing a row in the database.

Parameters:

table - the table in which to replace the row

nullColumnHack - 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 - this map contains the initial column values for the row. The key

Returns:

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

Throws:

SQLException

insertWithOnConflict

public long insertWithOnConflict(java.lang.String table,
                                 java.lang.String nullColumnHack,
                                 ContentValues initialValues,
                                 int conflictAlgorithm)

General method for inserting a row into the database.

Parameters:

table - the table to insert the row into

nullColumnHack - 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 - this map contains the initial column values for the row. The keys should be the column names and the values the column values

conflictAlgorithm - for insert conflict resolver

Returns:

the row ID of the newly inserted row OR the primary key of the existing row if the input param 'conflictAlgorithm' = CONFLICT_IGNORE OR -1 if any error

delete

public int delete(java.lang.String table,
                  java.lang.String whereClause,
                  java.lang.String[] whereArgs)

Convenience method for deleting rows in the database.

Parameters:

table - the table to delete from

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

whereArgs - You may include ?s in the where clause, which will be replaced by the values from whereArgs. The values will be bound as Strings.

Returns:

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.

update

public int update(java.lang.String table,
                  ContentValues values,
                  java.lang.String whereClause,
                  java.lang.String[] whereArgs)

Convenience method for updating rows in the database.

Parameters:

table - the table to update in

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

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

whereArgs - You may include ?s in the where clause, which will be replaced by the values from whereArgs. The values will be bound as Strings.

Returns:

the number of rows affected

updateWithOnConflict

public int updateWithOnConflict(java.lang.String table,
                                ContentValues values,
                                java.lang.String whereClause,
                                java.lang.String[] whereArgs,
                                int conflictAlgorithm)

Convenience method for updating rows in the database.

Parameters:

table - the table to update in

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

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

whereArgs - You may include ?s in the where clause, which will be replaced by the values from whereArgs. The values will be bound as Strings.

conflictAlgorithm - for update conflict resolver

Returns:

the number of rows affected

execSQL

public void execSQL(java.lang.String sql)
             throws SQLException

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(String, String, ContentValues), update(String, ContentValues, String, 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()

Parameters:

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

Throws:

SQLException - if the SQL string is invalid

execSQL

public void execSQL(java.lang.String sql,
                    java.lang.Object[] bindArgs)
             throws SQLException

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

For INSERT statements, use any of the following instead.

• insert(String, String, ContentValues)
• insertOrThrow(String, String, ContentValues)
• insertWithOnConflict(String, String, ContentValues, int)

For UPDATE statements, use any of the following instead.

• update(String, ContentValues, String, String[])
• updateWithOnConflict(String, ContentValues, String, String[], int)

For DELETE statements, use any of the following instead.

• delete(String, String, String[])

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()

Parameters:

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

bindArgs - only byte[], String, Long and Double are supported in bindArgs.

Throws:

SQLException - if the SQL string is invalid

isReadOnly

public boolean isReadOnly()

Returns true if the database is opened as read only.

Returns:

True if database is opened as read only.

isInMemoryDatabase

public boolean isInMemoryDatabase()

Returns true if the database is in-memory db.

Returns:

True if the database is in-memory.

isOpen

public boolean isOpen()

Returns true if the database is currently open.

Returns:

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

needUpgrade

public boolean needUpgrade(int newVersion)

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

Parameters:

newVersion - The new version code.

Returns:

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

getPath

public final java.lang.String getPath()

Gets the path to the database file.

Returns:

The path to the database file.

setLocale

public void setLocale(java.util.Locale locale)

Sets the locale for this database. This will be used by JSON Collator.

Parameters:

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.

setMaxSqlCacheSize

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 - the size of the cache. can be (0 to MAX_SQL_CACHE_SIZE)

Throws:

java.lang.IllegalStateException - if input cacheSize > MAX_SQL_CACHE_SIZE.

setForeignKeyConstraintsEnabled

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.

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 - True to enable foreign key constraints, false to disable them.

Throws:

java.lang.IllegalStateException - if the are transactions is in progress when this method is called.

enableWriteAheadLogging

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(com.couchbase.lite.internal.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(java.lang.String, com.couchbase.lite.internal.database.sqlite.SQLiteDatabase.CursorFactory, int). This is more efficient than calling enableWriteAheadLogging().

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

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:

True if write-ahead logging is enabled.

Throws:

java.lang.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.

See Also:

ENABLE_WRITE_AHEAD_LOGGING, disableWriteAheadLogging()

disableWriteAheadLogging

public void disableWriteAheadLogging()

This method disables the features enabled by enableWriteAheadLogging().

Throws:

java.lang.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.

See Also:

enableWriteAheadLogging()

isWriteAheadLoggingEnabled

public boolean isWriteAheadLoggingEnabled()

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

Returns:

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

See Also:

enableWriteAheadLogging(), ENABLE_WRITE_AHEAD_LOGGING

getAttachedDbs

public java.util.List<Pair<java.lang.String,java.lang.String>> getAttachedDbs()

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

Returns:

ArrayList of pairs of (database name, database file path) or null if the database is not open.

isDatabaseIntegrityOk

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:

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

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object