vb.org Archive - View Single Post - SQL optimization: "multiple queries" vs. "big join"

Eikinskjaldi · #10 08-01-2007, 09:05 PM

Quote:

Originally Posted by mihai11

I do have a "WHERE" clause, but that is not of much help. If there are no errors in the database then each story MUST have a corresponding thread. The only thing that will actually limit the number of returned rows is a "LIMIT clause".

No, that is not how queries work. They use where to optimise. the explain will clearly show you this.

Quote:

I am using an index, but I do not agree with your conclusions.

They are not conclusions, they are facts. Use explain once or twice, and all will become clear.

Code:

mysqldump --opt --host=ABC-HOST -Q -uUSER -pPASSWORD db_name > db_file.sql

Ahh right, of course. I keep forgetting that works with innodb.

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