I have 16 million rows in these 2 tables in Drupal.My sites are slow and these 2 tables top the slow query log. Can I safely truncate them?
Also, issuing a truncate command, hangs the system. Is there a way I can delete rows in batches?
+3
A:
Watchdog yes, Session has a timestamp that you should probably use to make sure any currently connected users don't lose their session. If you don't mind a little downtime, it might be worth it to turn the maintenance option on and then truncate both tables at a traffic-low/ appropriate time.
Al W
2010-10-22 04:37:40
@AW , Can you tell me of a way that I can delete rows in batches. Truncating the tables entirely causes the system to hang and the tables to crash.
Loveleen Kaur
2010-10-22 05:37:38
ok got it..limiting the rows when I delete them..thanks for the help.!
Loveleen Kaur
2010-10-22 05:58:07
+1
A:
You have an answer to your immediate problem, but dblog should be pruned automatically by cron. The number of rows to keep is a setting, admin/settings/logging/dblog
dblog can also be cleared and pruned to an extent with drush.
MPD
2010-10-22 18:59:20
A:
Watchdog and cache tables yes, but if you truncate session may be some users will lose their sessions.
Jose Daniel
2010-10-25 21:48:14