# START_TRANSACTION - start a transaction block - man(7) - [phpMan]

_START_ [_TRANSACTION_(7)](https://www.chedong.com/phpMan.php/man/TRANSACTION/7/markdown)               PostgreSQL 16.14 Documentation               _START_ [_TRANSACTION_(7)](https://www.chedong.com/phpMan.php/man/TRANSACTION/7/markdown)

## 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 **was executed. This is the same as the **BEGIN **command.

## PARAMETERS
       Refer to SET TRANSACTION ([**SET_TRANSACTION**(7)](https://www.chedong.com/phpMan.php/man/SETTRANSACTION/7/markdown)) 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 DEFERRABLE _transaction_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)](https://www.chedong.com/phpMan.php/man/SETTRANSACTION/7/markdown)).

## SEE ALSO
       [**BEGIN**(7)](https://www.chedong.com/phpMan.php/man/BEGIN/7/markdown), [**COMMIT**(7)](https://www.chedong.com/phpMan.php/man/COMMIT/7/markdown), [**ROLLBACK**(7)](https://www.chedong.com/phpMan.php/man/ROLLBACK/7/markdown), [**SAVEPOINT**(7)](https://www.chedong.com/phpMan.php/man/SAVEPOINT/7/markdown), SET TRANSACTION ([**SET_TRANSACTION**(7)](https://www.chedong.com/phpMan.php/man/SETTRANSACTION/7/markdown))

PostgreSQL 16.14                                2026                            _START_ [_TRANSACTION_(7)](https://www.chedong.com/phpMan.php/man/TRANSACTION/7/markdown)