Rate-limiting query execution in a batch process

Question

I have a set of queries in my queries.sql file which I am feeding to psql for execution. But I don't want them to run instantly one after the other: I would like to set some sort of delay - I was looking at \watch and query buffer but I am not so sure how to proceed. I would prefer not to write PG_SLEEP after each of my queries.

Answer 1

\watch executes the query buffer (one statement). It doesn't loop through different statements.

\set title "EVAN SAYS HAI"
SELECT 'HELLO WORLD' AS "Evan Greets the Plebs";
\watch

Now move that window over to your fifth monitor and when the boss comes by pretend like you're waiting for it to change.

If you want to put a delay in between query executions, make a spool as @Craig Ringer said in the comments

Write a Python or Perl script with your list of queries and have it loop over them, sleeping after each execution. – Craig Ringer Mar 5 at 11:18

You can do it one line or whatever too..

echo -e "SELECT 1;\nSELECT 2;\nSELECT 3;" |
  perl -pe'$|=1; sleep 1;' |
  psql -d foo;