![]() If the AUTOINCREMENT keyword appears after INTEGER PRIMARY KEY, thatĬhanges the automatic ROWID assignment algorithm to prevent the reuse of ROWIDs over the lifetime of the database. In order to prevent reuse of deleted values, the column must instead be created with type integer PRIMARY KEY AUTOINCREMENT. The only case where storing non-meaningful information makes sense is the special case that you want to have a synthetic primary key. This is true regardless of whether or not the AUTOINCREMENT There is no such thing as a non-primary key alais for the ROWID, as by definition if the ROWID exists in the table, it IS the Primary Key for the table. 12 Why would you want to have an autoincrement column that is not the primary key If you want a column to be an autoincrement, by definition, you are not storing meaningful data in that column. 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. ![]() See the API documentation for Column including the toincrement flag, as well as the section on Sequence later in this chapter for background on standard primary key generation techniques. 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 Is it possible to have a non-primary key to be auto-incremented with every insertion For example, I want to have a log, where every log entry has a primary key. For primary key columns, SQLAlchemy will in most cases use these capabilities automatically. Star 12.6k Code Issues 1. ![]() The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, andĭisk I/O overhead and should be avoided if not strictly needed. Star 12.6k Code Issues 1. ![]() Here is what official SQLite documentation has to say on the subject (bold & italic are mine): ![]()
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