Like others have mentioned, having a select followed by an insert/update based on that value is a race condition waiting to happen.

One fairly cross-platform solution is to do "SELECT foo FROM bar FOR UPDATE" which places an exclusive/write lock on the row. This works for Oracle, MySQL, PostgreSQL, Sybase, and MS SQL Server, according to my experience + a quick Google.

Tragically it doesn't seem to work in SQLite :)

/J

In reply to Re^2: Sequences, last_insert_id, SQLite, and Oracle by jplindstrom
in thread Sequences, last_insert_id, SQLite, and Oracle by gaal

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