Subject | Re: [firebird-support] Re: Performance Penalty for String Joins? |
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Author | Helen Borrie |
Post date | 2004-03-09T06:13:04Z |
At 05:05 AM 9/03/2004 +0000, you wrote:
known, it doesn't have to be stored with the data - that's what char is for.
Varchar works OK, and it might actually be more useful, e.g. where codes
from different barcode systems are being read into the same column
(sometimes a requirement). I've certainly worked with more than one setup
where the barcode is a varchar (30) and there is a second column that
carries a code identifying which barcode system it belongs to--with a
unique constraint on the two.
/heLen
>I'm in the habit (maybe a bad one) of just using VARCHAR. What is theFor fixed-length data, it's more compact. Since the length f/l data is
>advantage to CHAR?
known, it doesn't have to be stored with the data - that's what char is for.
Varchar works OK, and it might actually be more useful, e.g. where codes
from different barcode systems are being read into the same column
(sometimes a requirement). I've certainly worked with more than one setup
where the barcode is a varchar (30) and there is a second column that
carries a code identifying which barcode system it belongs to--with a
unique constraint on the two.
/heLen