Unique ROWIDs as long as you never use the maximum ROWID value and you neverĭelete the entry in the table with the largest ROWID. R-60470-29837:[ The normal ROWID selection algorithm described above Generated ROWID values will always be greater than zero. ] R-40812-03570:[ If no negative ROWID values are inserted explicitly, then automatically The insert operation fails with an SQLITE_FULL error. ] R-38219-53002:[ If no unused ROWID can be found after a reasonable number of attempts, ] R-07677-41881:[ If the largest ROWID is equal to the largest possible integerĮngine starts picking positive candidate ROWIDs at random until it finds one ] R-61914-48074:[ If the table is initially empty, then a ROWID of 1 is
] R-29538-34987:[ The usual algorithm is to give the newly created rowĪ ROWID that is one larger than the largest ROWID in the table prior
Of NULL, then an appropriate ROWID is createdĪutomatically. R-12104-35971:[ If no ROWID is specified on the insert, or if the specified ROWID has a value INSERT INTO test1(rowid, a, b) VALUES(123, 5, 'hello') Just include it in the list of values to be inserted. R-54260-17937:[ When a new row is inserted into an SQLite table, the ROWID can eitherīe specified as part of the INSERT statement or it can be assignedĪutomatically by the database engine. ] R-37283-61388:[ All these names areĪliases for one another and work equally well in any context. Or the name given to the INTEGER PRIMARY KEY column. Using any of four different names, the original three names described above ] R-05038-25064:[ You can then access the ROWID R-38485-20010:[ If a table contains a column of type INTEGER PRIMARY KEY, then thatĬolumn becomes an alias for the ROWID. Names, then the use of that name will refer to the declared column not R-23612-42210:[ You can access the ROWID of an SQLite table using one of the special columnĮxcept if you declare an ordinary table column to use one of those special ( WITHOUT ROWID tables are the exception.) Which is unique among all rows in the same table. R-28870-48866:[ In SQLite, table rows normally have a 64-bit signed integer ROWID The purpose of AUTOINCREMENT is to prevent the reuse of ROWIDs from The reuse of ROWIDs over the lifetime of the database. If the AUTOINCREMENT keyword appears after INTEGER PRIMARY KEY, thatĬhanges the automatic ROWID assignment algorithm to prevent This is true regardless of whether or not the AUTOINCREMENT keyword is used. One more than the largest ROWID currently in use. Will be filled automatically with an unused integer, usually On an INSERT, if the ROWID or INTEGER PRIMARY KEY column is not (except in WITHOUT ROWID tables) which is always a 64-bit signed integer. In SQLite, a column with type INTEGER PRIMARY KEY is an alias for the ROWID The AUTOINCREMENT keyword imposes extra CPU, memory, disk space,Īnd disk I/O overhead and should be avoided if not strictly needed.
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