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From:Johan De Meersman Date:June 25 2010 9:13am
Subject:Re: Altering database size to add more space
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On Fri, Jun 25, 2010 at 7:11 AM, Prabhat Kumar <aim.prabhat@stripped>wrote:

> In case MyISAM it will grow up to space on your data drive or the Max size
> of file limited by OS..
>


Not entirely correct. There is some kind of limit to a MyISAM file that has
to do with pointer size - I've encountered it several years ago.

You shouldn't be encountering it, in most circumstances, but that's what the
max_data_length column in *show table status* is about.

Before 5.0.6, the default max datafile size was 4G, but that's been upped to
256T now.

If you're really running in to this have a look at the various advanced
options for create/alter table, like avg_row_length and max_rows; as well as
the variable myisam_data_pointer_size.

Now what Sarkis is running into, is more of a logical error: data_free does
not tell you how much free space there is *for data*, but how much free
space there is *in the existing datafile*. That is, it really tells you how
much space in your file has become free by deleting rows et al. This also
explains why it's always 0 for InnoDB tables :-)


-- 
Bier met grenadyn
Is als mosterd by den wyn
Sy die't drinkt, is eene kwezel
Hy die't drinkt, is ras een ezel

Thread
Altering database size to add more spaceSarkis Karayan24 Jun
  • Re: Altering database size to add more spaceAnanda Kumar24 Jun
  • Re: Altering database size to add more spaceJim Lyons24 Jun
    • Re: Altering database size to add more spacePrabhat Kumar25 Jun
      • Re: Altering database size to add more spaceJohan De Meersman25 Jun
        • Re: Altering database size to add more spaceJim Lyons25 Jun
          • Re: Altering database size to add more spaceCarsten Pedersen25 Jun