Re: Table with 90 columns
От | Ligia Pimentel |
---|---|
Тема | Re: Table with 90 columns |
Дата | |
Msg-id | F89TJby0LKhogUojTpe0000eec9@hotmail.com обсуждение исходный текст |
Ответ на | Table with 90 columns (Michael und Katrin Rudolph <MuK.Rudolph@t-online.de>) |
Список | pgsql-general |
Hi. You are right, if you are always using always all 90 fields of the record and if it is normalized means you would have to make a lot of joins with other tables, but, MY THEORY is that if the records are longer, the buffer will read less records each time you access (physically) the disk, and (even on an optimally indexed table, you will have more disk access, so it wil be slower. Of course, this could be set up by fixing buffer sizes, but... I would always suspect a table with 90 columns has a lot of redundancy on it, and you will find other problems later, (again, I work by this rule...). Anyway, On this case, I think that changing the database structure would imply changes on the server side, not on the client side (unless all the logic of the application is on the client-side, on user pages) which is not desirable... again and this is MY THEORY, I would use server side components (java servlets, ISAPIs, or something like that) which would make your application more manageable,... On the other side, remember, If you give the same problem to 10 software engineers, you would surelly get 10 different solutions, so, I guess, if it works for you... Ligia You wrote... >As far as I understand normalization it is meant to avoid *redundance* and >not to improve performance. Actually normalization in general decreases >performance becaus a join over several tables is much less efficient than a >select on a single table. _________________________________________________________________ Join the world�s largest e-mail service with MSN Hotmail. http://www.hotmail.com
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