Subject | Re: [Firebird-Architect] Re: UTF-8 (various) |
---|---|
Author | Alexandre Benson Smith |
Post date | 2005-03-04T06:27:25Z |
Jim Starkey wrote:
Of course a slow right answer is better than fast wrong one, but I think
that if all queries does a natural scan on tables to perform the
collation analises on run-time will not work either.
If I understand right, will be a problem on how to create indices if we
have a common chasert inside de engine and how those index will be
evaluated with different charsets/collations define by sessions
(queries), taking this, won't be enough if the create index statement to
have another clause the specifies the collation order ?
Something like
Create index MyIndex on MyTable(MyColumnA) collate PT_BR
When the query will be execute using a charset ISO8859_1 and PT_BR
collation the index could be used, if another session (query ?) execute
the same query but uses a diferent charset/collation the index coud not
be used.
Or is this nonsense ?
see you !
--
Alexandre Benson Smith
Development
THOR Software e Comercial Ltda.
Santo Andre - Sao Paulo - Brazil
www.thorsoftware.com.br
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>Collation is also requires to evaluate greater than / less than. TheJim,
>collation that a program is expecting is a great deal more important
>than how a particular index was defined. It boils down to the
>fundamental question: Which is more important, going fast or getting the
>right answer. If the pick the former, all queries can return 13.
>
>
Of course a slow right answer is better than fast wrong one, but I think
that if all queries does a natural scan on tables to perform the
collation analises on run-time will not work either.
If I understand right, will be a problem on how to create indices if we
have a common chasert inside de engine and how those index will be
evaluated with different charsets/collations define by sessions
(queries), taking this, won't be enough if the create index statement to
have another clause the specifies the collation order ?
Something like
Create index MyIndex on MyTable(MyColumnA) collate PT_BR
When the query will be execute using a charset ISO8859_1 and PT_BR
collation the index could be used, if another session (query ?) execute
the same query but uses a diferent charset/collation the index coud not
be used.
Or is this nonsense ?
see you !
--
Alexandre Benson Smith
Development
THOR Software e Comercial Ltda.
Santo Andre - Sao Paulo - Brazil
www.thorsoftware.com.br
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.300 / Virus Database: 266.5.7 - Release Date: 01/03/2005