Contents
transaction_timestamp()
A function returning the point-in-time the current transaction started
transaction_timestamp() is a system function returning a timestamp representing the point-in-time at which the current transaction started.
transaction_timestamp() was added in PostgreSQL 8.2.
Usage
transaction_timestamp ( ) → timestamp with time zone
Historically the function current_timestamp returned the start time of the current transaction; transaction_timestamp() was added as a less ambiguous alias.
Change history
- PostgreSQL 8.2
- added (commit e6004f01)
Examples
Basic execution example for transaction_timestamp():
postgres=# BEGIN;
BEGIN
postgres=*# SELECT transaction_timestamp(), statement_timestamp();
transaction_timestamp | statement_timestamp
-------------------------------+-------------------------------
2021-06-17 18:22:12.555089+01 | 2021-06-17 18:23:17.327421+01
(1 row)
If a statement is executed outside of an explicit transaction, the timestamp returned by transcation_timestamp()is identical to that returned by statement_timestamp():
postgres=# SELECT transaction_timestamp(), statement_timestamp();
transaction_timestamp | statement_timestamp
------------------------------+------------------------------
2021-06-17 18:24:27.91313+01 | 2021-06-17 18:24:27.91313+01
(1 row)
References
- PostgreSQL documentation: Date/Time Functions
- PostgreSQL documentation: Current Date/Time