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18.2.4 Use shorter queries where possible

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"DELETE FROM usertable;" is much (much!) faster than "DELETE FROM usertable WHERE Name LIKE '%';" simply because MySQL actually sits and compares each name to % (remember that a percent sign (%) means "anything, so MySQL matches all names)

<< 18.2.3 Select as little data as possible		18.2.5 Use the EXPLAIN statement >>
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A PHP User - 13 Oct 2008

He was trying to prove a point...

A PHP User - 13 Oct 2008

Is this a book for dummies? Who was going to write LIKE '%"? I do not think it's a good example for "using shorter queries"...

alapidus1215@gmail.com - 13 Oct 2008

There is a difference: TRUNCATE resets auto-increment to 1; DELETE does not.

A PHP User - 13 Oct 2008

I think "TRUNCATE TABLE usertable;" is faster than "DELETE FROM usertable;".

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