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From:Michael Widenius Date:August 2 1999 12:24am
Subject:Re: MyISAM vs ISAM
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>>>>> "jgauthier" == jgauthier  <jgauthier@stripped>
> writes:

>> 
>> mysql uses that same C API; perhaps it's a problem with the way you're
>> doing the selects?
>> 


jgauthier> I do not know. I run my application, which records the select times.
jgauthier> convert the database and then run it again.  Pretty simple selects too.

hi!

To be able to help you, we would need some examples!

I have found one bug in MySQL;  A memory leak involving updates of
blobs.  Apart from that the only major issue seams to be that if you
use packed keys, then MyISAM may be slower (depending on what you do
with your table).  You can force MyISAM to not pack keys with:

CREATE TABLE ... PACK_KEYS=0

and force it to pack keys even more:

CREATE TABLE ... PACK_KEYS=1

If you don't specify PACK_KEYS then only some selected keys will be packed.

Depending on what you do, either of the above should give you
identical (or better) performance than ISAM.

I haven't yet got a full test case for a case when MyISAM is slower
than ISAM, so I can't comment on when this would happen.

Note that if you run myisamchk on a table (before MySQL 3.23.2), you
must always use the -a switch (if not, MySQL will may not use keys in
future selects)

MyISAM has a lot of new nice functionality and over time it will
make the old ISAM obsolete.

Regards,
Monty
Thread
MyISAM vs ISAMjgauthier23 Jul
  • Re: MyISAM vs ISAMMark Papadakis23 Jul
Re: MyISAM vs ISAMPaul DuBois23 Jul
  • Re: MyISAM vs ISAMjgauthier23 Jul
    • Re: MyISAM vs ISAMMichael Widenius2 Aug