table of contents
START TRANSACTION(7) | PostgreSQL 9.2.24 Documentation | START TRANSACTION(7) |
NAME¶
START_TRANSACTION - start a transaction block
SYNOPSIS¶
START TRANSACTION [ transaction_mode [, ...] ] where transaction_mode is one of:
ISOLATION LEVEL { SERIALIZABLE | REPEATABLE READ | READ COMMITTED | READ UNCOMMITTED }
READ WRITE | READ ONLY
[ NOT ] DEFERRABLE
DESCRIPTION¶
This command begins a new transaction block. If the isolation level, read/write mode, or deferrable mode is specified, the new transaction has those characteristics, as if SET TRANSACTION (SET_TRANSACTION(7)) was executed. This is the same as the BEGIN(7) command.
PARAMETERS¶
Refer to SET TRANSACTION (SET_TRANSACTION(7)) for information on the meaning of the parameters to this statement.
COMPATIBILITY¶
In the standard, it is not necessary to issue START TRANSACTION to start a transaction block: any SQL command implicitly begins a block. PostgreSQL's behavior can be seen as implicitly issuing a COMMIT after each command that does not follow START TRANSACTION (or BEGIN), and it is therefore often called “autocommit”. Other relational database systems might offer an autocommit feature as a convenience.
The DEFERRABLEtransaction_mode is a PostgreSQL language extension.
The SQL standard requires commas between successive transaction_modes, but for historical reasons PostgreSQL allows the commas to be omitted.
See also the compatibility section of SET TRANSACTION (SET_TRANSACTION(7)).
SEE ALSO¶
BEGIN(7), COMMIT(7), ROLLBACK(7), SAVEPOINT(7), SET TRANSACTION (SET_TRANSACTION(7))
2017-11-06 | PostgreSQL 9.2.24 |