Re: performace review

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От Alexander Staubo
Тема Re: performace review
Дата
Msg-id A94CC970-36F0-4BD2-A37D-DC4777CEDF8F@purefiction.net
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Ответ на Re: performace review  ("Brandon Aiken" <BAiken@winemantech.com>)
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On Oct 7, 2006, at 23:44 , Brandon Aiken wrote:

> I download the db source (inside opencrx-1.9.1-
> core.postgresql-8.zip) and executed their three schema files,
> dbcreate-indexes.sql, dbcreate-views.sql, dbcreate-tables.sql.
> Each of the 118 tables has a three-field composite primary key of
> 'PRIMARY KEY (object_rid, object_oid, object_idx)'.  object_rid and
> object_oid are both VARCHAR(200).  There are *no* foreign key
> constraints.  Each table has between 15 and 50 fields, with 25
> looking about average.

To be fair, there are a bunch of indexes, but the number of indexes
seems low compared to the number of fields.

> Gee, why to table joins take so long?  Maybe because a blind monkey
> created the schema?  Normalized databases do tend to perform
> better, so I hear.

*De*normalization is the traditional hack to speed up queries,
because it reduces the need for joins.

Alexander.



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