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Is there a difference between these two where clauses in terms of speed? Are the column still indexed in the second one?
1. SELECT * FROM TableName WHERE col1 = 'a' AND col2 = 'b' AND col3='c'
2. SELECT * FROM TableName WHERE (col1,col2,col3) = ('a','b','c')
When
PRIMARY KEY (col1,col2,col3)
Thanks
There shouldn’t be, but you can use EXPLAIN to find out in the context of your database.