Youmay wonder, how long has it been since the server started?
For instance, you might want to verify that there was no server crash if your server is not monitored; or to see when the server was last restarted, for instance, to change the configuration. We will find this out by asking the database server.
Issue the following SQL from any interface:
postgres=# SELECT date_trunc('second', current_timestamp - pg_postmaster_start_time()) as uptime;You should get the output as follows:
uptime -------------------------------------- 2 days 02:48:04
Postgres stores the server start time, so we can access it directly, as follows:
postgres=# SELECT pg_postmaster_start_time(); pg_postmaster_start_time ---------------------------------------------- 2018-01-01 19:37:41.389134+00
Then, we can write a SQL query to get the uptime, like this:
postgres=# SELECT current_timestamp - pg_postmaster_start_time();
?column?
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