Is it possible to write data to postgres temporarily?

Question

PostgreSQL

Is it possible to assign the value true to any variable, and after 3 hours it is independently redefined to false?

Answer 1

for such a task, not boolean is written to the database, but the time at the time of recording, and in the select query they do
select now()-start_time<=3 часа from ....

Answer 2

It is possible, but for this you will have to write a stored procedure, and run it by distribution, using cron, or some extension.