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From:Jeremy Cole Date:January 18 2005 7:28pm
Subject:Re: Logging Data: Should I use MyIsam or InnoDB?
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Hi Thomas,

> I have a curious issue here, maybe someone can help.
> 
> I have a single process that inserts data into tables that contain
> purely logging information.  This table is then searched by our Care
> department to troubleshoot issues.  I am looking for the best way to
> store this data, and the structure on the backend.
> 
> There are 50 million inserts into table LOG a day.  The primary index
> on the table is seconds from 1971.  I only need to keep 60 days worth
> of data, and the table is only used for read purposes.  This is my
> design criteria, but my problem is how to delete old data without
> crashing the log writer that is atteched to the table.

OK, how about this:

Use MyISAM and MERGE tables.  Keep one table per day.  E.g.:

log_2005_01_15
log_2005_01_16
log_2005_01_17
log_2005_01_18

etc.

Use MERGE tables to give you the 60 day (and perhaps e.g. 14 day, 30 
day, 7 day, etc.) read views that you need, like so:

CREATE TABLE log_view_7day (
   ...
) TYPE=MERGE UNION=(
   log_2005_01_12,
   log_2005_01_13,
   log_2005_01_14,
   log_2005_01_15,
   log_2005_01_16,
   log_2005_01_17,
   log_2005_01_18
);

Create another MERGE table for "today" using INSERT_METHOD:

CREATE TABLE log_view_today (
   ...
) TYPE=MERGE INSERT_METHOD=FIRST UNION=(
   log_2005_01_18
);

You can then do all of your inserts from the log writer into the "today" 
table, and do your reads against the various MERGEs.

Every day at exactly midnight, you would use ALTER TABLE (which is 
atomic) to redefine the UNION of the MERGE definition of the various tables.

When you want to delete your "old" data, it's simply a matter of doing 
an ALTER TABLE to remove them from the MERGE, and using DROP TABLE to 
drop the log_yyyy_mm_dd table after that.

Also note that you could compress the old data and leave it live (but 
read only) in case you ever need it.  myisampack can help you with that.

I hope that helps!

Regards,

Jeremy

-- 
Jeremy Cole
Technical Yahoo - MySQL (Database) Geek
Thread
Logging Data: Should I use MyIsam or InnoDB?Thomas Lekai18 Jan
  • Re: Logging Data: Should I use MyIsam or InnoDB?Jeremy Cole18 Jan
  • Re: Logging Data: Should I use MyIsam or InnoDB?Martijn Tonies19 Jan
    • Re: Logging Data: Should I use MyIsam or InnoDB?Javier Armend├íriz19 Jan
    • Re: Logging Data: Should I use MyIsam or InnoDB?SGreen19 Jan
      • Re: Logging Data: Should I use MyIsam or InnoDB?Martijn Tonies19 Jan
RE: Logging Data: Should I use MyIsam or InnoDB?Thomas Lekai18 Jan
  • Re: Logging Data: Should I use MyIsam or InnoDB?Jeremy Cole18 Jan
RE: Logging Data: Should I use MyIsam or InnoDB?Thomas Lekai18 Jan