Delay or Wait-For Statement

问题

I have a 500,000 line SQL script:

update users set region_id = 9814746 where id = 101 and region_id is null;
update users set region_id = 9814731 where id = 102 and region_id is null;
update users set region_id = 3470676 where id = 103 and region_id is null;

I want to INSERT a delay of 10 seconds every 50 lines. Does pgsql have a waitfor statement like t-sql.

Thanks.

回答1:

Does pgsql have a waitfor statement like t-sql.

Yes, pg_sleep:

pg=> SELECT pg_sleep(10);
 pg_sleep 
----------

(1 row)

回答2:

You could call the pg_sleep function with the PERFORM statement since we don't care about returning values:

PERFORM pg_sleep(10);

回答3:

Not to my knowledge.

You could do something in the shell, piping your SQL through a simple script and then into PostgreSQL. E.g. with Perl:

cat regionupdates.sql | perl -e '$i = 1; while(<STDIN>) { $i++; print $_; if ($i % 50 == 0) { sleep 10; } }' | psql -d MYDB -L output.txt

BTW: I see you asked a very similar question before. It would be nice if you could accept the answers you found solved your problem:

Begin...commit every 50 rows

来源：https://stackoverflow.com/questions/1331409/delay-or-wait-for-statement