PostgreSQL pg_sleep_for() Function

The PostgreSQL pg_sleep_for() function receives an interval parameter that pauses the execution of the current server process for the specified interval.

pg_sleep_for() Syntax

Here is the syntax of the PostgreSQL pg_sleep_for() function:

pg_sleep_for(duration INTERVAL)

Parameters

duration

Required. A value of INTERVAL type that indicates how long the current server process is paused.

Return value

The PostgreSQL pg_sleep_for() function has no return value, it is used to suspend the execution of the current server process for the specified interval.

pg_sleep_for() Examples

This example combined clock_timestamp() demonstrates the capabilities of pg_sleep_for().

SELECT
    clock_timestamp(),
    pg_sleep_for('10 seconds'),
    clock_timestamp();

-[ RECORD 1 ]---+------------------------------
clock_timestamp | 2022-05-20 11:31:05.691725+08
pg_sleep_for    |
clock_timestamp | 2022-05-20 11:31:15.695237+08

here:

  • We use an interval value 10 seconds for pg_sleep_for(), which is used to pause the current server process for 10 seconds.
  • Since we use pg_sleep_for('10 seconds') in the middle of the two clock_timestamp() functions to pause the execution of current server process for 10 seconds, so the execution of the second clock_timestamp() function is 10 seconds later than the first, so the return value of the second is 10 seconds later than the first.