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From:Chuck Gadd Date:December 5 2003 7:48am
Subject:Re: Large data set load and access
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beacker@stripped wrote:

>      Thanks for the heads up on this.  Unfortunately the only
> varchar is the gbl_locus field, so I'm not sure how much this
> would by me for the space.
>                Thanks again,
>                        Brad Eacker (beacker@stripped)

No, it wouldn't save you any space.  It would make your file a
little bigger on the drive.  varchar is a variable length
field.  As you've got it now, if you store a 10 byte string in
that field, it'll only take up something like 14 bytes.   If
you store 1 character, it'll take up 5 bytes.  So you are
currently saving a little space.

BUT!  Variable length fields slow Mysql down a little bit when
it's reading the table, since Mysql needs to read in each
record completely to get to the next record.  If you have no
variable length fields, then mysql can calculate right away the
starting position of any record based on the fixed record size.






Thread
Large data set load and accessbeacker4 Dec
  • Re: Large data set load and accessChuck Gadd5 Dec
Re: Large data set load and accessbeacker5 Dec
  • Re: Large data set load and accessChuck Gadd5 Dec