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Is there any performance difference between query A and query B?
Query A
SELECT * FROM SomeTable
WHERE 1 = 1 AND (SomeField LIKE '[1,m][6,e][n]%')
Query B
SELECT * FROM SomeTable
WHERE 1 = 1 AND (SomeField IN ('16', 'Mens'))
The first could be much slower. An index can’t be used with
LIKEunless there is a constant prefix, for exampleLIKE 'foo%'. The first query will therefore require a table scan. The second query however could use an index onSomeFieldif one is available.The first query will also give the wrong results as it matches ‘1en’.