Explicit locking mechanism in SQLite

Question

I did not find explicit sqlite locking commands before inserting or updating rows into the table. Does sqlite handle the locking mechanism on it own? The pager module descr

Answer 1

SQLite does whatever locking is necessary in order to implement the transaction scheme that your SQL statements describe. In particular, if you don't describe any then you get auto-commit behavior, with a lock held for the duration of each statement and then dropped as the statement finishes. Should you need longer transactions (often true!) then you ask for them explicitly with BEGIN TRANSACTION (often shortened to BEGIN) and finish with COMMIT TRANSACTION (or ROLLBACK TRANSACTION). The transaction handling is frequently wrapped for you by your language interface (as this makes it considerably easier to get right, coupling the transaction lifetime to a code block or method call) but at the base level, it comes down to BEGIN/COMMIT/ROLLBACK.

In short, you've got transactions. Locks are used to implement transactions. You don't have raw locks (which is a good thing; they're rather harder to get right than you might think from first glance).