Richard Warr (1/30/2015)
Michel Steiner (1/30/2015)
Under which conditions can count(*) be slow? I'm trying with a 5TB DB, several tables having millions of rows and always get the answer in less than 1 sec.When you don't have an index.
But the point is that count(*) is no different performance wise than count(1). If there is no index the performance is the same.
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