SQLite: are pragma statements undone by rolling back transactions?

Just wondering whether pragmas such as foreign_keys = OFF, and VACUUM would be undone if included in a transaction 开发者_如何学编程which gets rolled back.

The online documentation doesn't seem to cover this...

It is different for different pragma statements.

For example, SQLite version 3.7.15.2 includes the pragma 'user_version' in transactions and will COMMIT and ROLLBACK the value.

However, the same version of SQLite specifically excludes (in documentation and testing) foreign_keys from transactions.

It appears, from my limited sampling, that pragma that are not documented as invalid during transactions (foreign_key) will participate in the transaction (like user_version.)

PS: I realize this is a very old question, but it is where Google brought me when I needed this information.

The documentation does not cover what happens with pragma statements issued inside transactions in general, but it does cover the subject for foreign_keys (and possibly for others):

This pragma is a no-op within a transaction; foreign key constraint enforcement may only be enabled or disabled when there is no pending BEGIN or SAVEPOINT.

VACUUM is not a pragma, and the documentation does cover transactions:

A VACUUM will fail if there is an open transaction, or if there are one or more active SQL statements when it is run.

I can verify that at least the following PRAGMA is not valid within a transaction:

PRAGMA journal_mode=WAL;

If attempted, you will receive some flavor of the following error message:

SQL logic error: cannot change into wal mode from within a transaction