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From:Wm Mussatto Date:July 20 2007 8:41pm
Subject:Re: MySQL slow when altering tables.
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On Fri, July 20, 2007 12:32, Andrew Rosolino said:
> Whenever I alter a mysql table like add a new field it gets really slow
> and
> all other processes lag.
> Is there a memory variable I can adjust for this?
> --
> View this message in context:
Without more information it might be hard to answer.  A general though:
Alter Table causes the entire table to be re-created in its new form and
then the old one deleted and the new one renamed.  For a large table that
is a significant bit of work (cpu, disk  and memory).  It might help if
you could give the size of the table and what the alter involved (for
example generating a new index would take even more time).

William R. Mussatto
Systems Engineer

MySQL slow when altering tables.Andrew Rosolino20 Jul
  • Re: MySQL slow when altering tables.Wm Mussatto20 Jul
    • max_connect_errors Charles Brown23 Jul
  • Re: MySQL slow when altering tables.mos23 Jul