Disadvantage of SQL Joins

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От Ranjan Kumar Baisak
Тема Disadvantage of SQL Joins
Дата
Msg-id 456DA978.2020407@nyc.yamaha.com
обсуждение исходный текст
Ответ на Re: backend crash following load command  ("Merlin Moncure" <mmoncure@gmail.com>)
Ответы Re: Disadvantage of SQL Joins  (Scott Ribe <scott_ribe@killerbytes.com>)
Список pgsql-general
Can anybody please tell me whether there are any disadvantage of SQL
joins in terms of space and time and how postgres has implemented SQL
joins? I am in the impression that SQL join takes more time for
execution as well as space because database internally builds Cartesian
product and then evaluates for condition. Recently I normalized by DB
and changed my application Data model which resulted in writing lots of
inner join queries. Later I found that DB server is consuming more
memory. And once my Database also crashed. I am assuming that because of
normalization and inner joins, my DB crashed.
Can anybody please give a thought into my assumption?

- R

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