Each statement within SurrealDB is run within its own transaction by default. If a set of changes need to be made together, then groups of statements can be run together as a single transaction, either succeeding as a whole, or failing without leaving any residual data modifications. A COMMIT statement is used at the end of such a transaction to make the data modifications a permanent part of the database.
Statement syntax
COMMIT [ TRANSACTION ];Example usage
The following query shows example usage of this statement.
/**[test]
[[test.results]]
value = "NONE"
[[test.results]]
value = "[{ balance: 135605.16f, id: account:one }]"
[[test.results]]
value = "[{ balance: 91031.31f, id: account:two }]"
[[test.results]]
value = "[{ balance: 135905.16f, id: account:one }]"
[[test.results]]
value = "[{ balance: 90731.31f, id: account:two }]"
[[test.results]]
value = "NONE"
*/
BEGIN TRANSACTION;
-- Setup accounts
CREATE account:one SET balance = 135605.16;
CREATE account:two SET balance = 91031.31;
-- Move money
UPDATE account:one SET balance += 300.00;
UPDATE account:two SET balance -= 300.00;
-- Finalise all changes
COMMIT TRANSACTION;The following two options can be used at any point if a transaction must be cancelled without commiting the changes:
CANCEL to manually cancel the transaction.
THROW to cancel a transaction with an optional error message. THROW is the only way to cancel a transaction based on a condition, such as inside an IF..ELSE block.
In addition, a RETURN statement can be used to return early from a successful transaction. This is often used in order to return a customized output.
/**[test]
[[test.results]]
value = "'Money sent! Status:
{ balance: 135905.16f, id: account:one }
{ balance: 90731.31f, id: account:two, wants_to_send_money: true }'"
[[test.results]]
value = "{ balance: 135905.16f, id: account:one }"
[[test.results]]
value = "{ balance: 90731.31f, id: account:two, wants_to_send_money: true }"
*/
BEGIN;
CREATE account:one SET balance = 135605.16;
CREATE account:two SET balance = 91031.31, wants_to_send_money = true;
IF !account:two.wants_to_send_money {
THROW "Customer doesn't want to send any money!";
};
LET $first = UPDATE ONLY account:one SET balance += 300.00;
LET $second = UPDATE ONLY account:two SET balance -= 300.00;
RETURN "Money sent! Status:\n" + <string>$first + '\n' + <string>$second;
COMMIT;'Money sent! Status:
{ balance: 135905.16f, id: account:one }
{ balance: 90731.31f, id: account:two, wants_to_send_money: true }'