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Coordinator DB
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Transactions ​

A transaction groups changes into one unit of commit or rollback. Statements outside an explicit transaction autocommit.

Controls ​

Statement Effect
BEGIN Start a transaction.
COMMIT Keep its changes.
ROLLBACK Undo its changes.
SAVEPOINT name Create an inner undo point.
ROLLBACK TO name Undo later changes and retain that savepoint.
RELEASE name Remove the savepoint.

Example ​

Undoing one adjustment ​

sql
CREATE TABLE balances(id INTEGER PRIMARY KEY, amount INTEGER);
BEGIN;
INSERT INTO balances VALUES (1, 10);
SAVEPOINT adjustment;
UPDATE balances SET amount = 20;
ROLLBACK TO adjustment;
RELEASE adjustment;
COMMIT;
sql
SELECT id, amount
FROM balances
FORMAT csv;
text
1,10

The insert remains, while the adjustment after the savepoint is undone.

Connection scope ​

A native connection retains its open transaction. Closing it rolls back uncommitted changes.

Every HTTP request has a separate session. Put BEGIN, the related statements and COMMIT in one request; an unclosed transaction is rolled back before the response is sent.

Several connections in one process can share a file. Simultaneous access from separate processes is outside the supported concurrency model. See deployment modes.