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Re: Index Keys of the table
Posted by: Rick James
Date: November 02, 2012 08:21PM

There is a big difference between these:
WHERE name LIKE 'Lee%'
WHERE name LIKE '%Lee%'

The first one (without the leading wildcard) can use INDEX(name).
The second one cannot; it will scan the entire table (unless there is something else useful in the WHERE clause.

A full table scan of 405MB will be slow.

Based on your last comment, only WHERE DOB = '...' will be able to use an index.

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