So if a database will only be used by a single thread, or if optimizingĬoncurrency is not very important, then write-ahead logging should be disabled.Īfter calling this method, execution of queries in parallel is enabled as long as Journaling because there are multiple connections to the same database. However, write-ahead logging uses significantly more memory than ordinary It is a good idea to enable write-ahead logging whenever a database will beĬoncurrently accessed and modified by multiple threads at the same time. On other threads will then perceive the new state of the database. Of the database as it was before the write began. While a write is in progress, readers on other threads will perceive the state Operations occur in a separate log file which allows reads to proceed concurrently. In contrast, when write-ahead logging is enabled (by calling this method), write Prevents readers from accessing the database until the write is completed. Before modifying theĭatabase, the writer implicitly acquires an exclusive lock on the database which
Reads and writes to occur on the database at the same time. When write-ahead logging is not enabled (the default), it is not possible for Journal mode is also changed to enable writes to proceed concurrently with reads. It does this by opening multiple connections to the databaseĪnd using a different database connection for each query. This method enables parallel execution of queries from multiple threads on the The pattern) for certain pathological cases.ĪcquireNativeConnectionHandle(String operation, boolean readOnly, boolean interactive) Of SQLite can exhibit O(N^2) performance (where N is the number of characters in The pattern matching algorithm used in the default LIKE and GLOB implementation If the disk is full, this may fail even before you actually write anything. Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) to open the database for reading and writing. Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) to open the database for reading only.
Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) to open the database without support for Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) that indicates no backup for database files is Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) to open the database file withĪbsolute max value that can be set by setMaxSqlCacheSize(int). Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) to open the database with I/O trace enabled. Open flag: Flag for openDatabase(String, byte, SQLiteCipherSpec, SQLiteDatabase.CursorFactory, int, DatabaseErrorHandler) to create the database file if it does not Thus ending the current transaction, and the command aborts with a When a constraint violation occurs, an immediate ROLLBACK occurs, When a UNIQUE constraint violation occurs, the pre-existing rows thatĪre causing the constraint violation are removed prior to inserting Use the following when no conflict action is specified. The constraint violation is not inserted or changed. When a constraint violation occurs, the one row that contains When a constraint violation occurs, the command aborts with a return So changes from prior commands within the same transaction When a constraint violation occurs,no ROLLBACK is executed Used to allow returning sub-classes of Cursor when calling query.
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