In other words, the purpose of AUTOINCREMENT is to prevent the reuse of ROWIDs from previously deleted rows. If the AUTOINCREMENT keyword appears after INTEGER PRIMARY KEY, that changes the automatic ROWID assignment algorithm to prevent the reuse of ROWIDs over the lifetime of the database. This is true regardless of whether or not the AUTOINCREMENT keyword is used. On an INSERT, if the ROWID or INTEGER PRIMARY KEY column is not explicitly given a value, then it will be filled automatically with an unused integer, usually one more than the largest ROWID currently in use. In SQLite, a column with type INTEGER PRIMARY KEY is an alias for the ROWID (except in WITHOUT ROWID tables) which is always a 64-bit signed integer. The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, and disk I/O overhead and should be avoided if not strictly needed.
#Pdo sqlite autoincrement driver
Installation The PDOSQLITE PDO driver is enabled by default. Note: PDOSQLITE allows using strings apart from streams together with PDO::PARAMLOB. OMG Ponies at 21:07 what made you think they were the same Each RDBMS seems to have it's own little twist, so you are going to run into these kind of issues. Introduction PDOSQLITE is a driver that implements the PHP Data Objects (PDO) interface to enable access to SQLite 3 databases. It can be applied to a field when creating a table. SQLite AUTOINCREMENT documentation - autoincrement is not ANSI, sequences were only recently made ANSI for handling sequential value generation. The AUTOINCREMENT keyword can be used with INTEGER PRIMARY KEY field only. The SQLite AUTOINCREMENT is a keyword used for auto incrementing a value of a field in the table.
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