So what IS the best way to check if a row exists? EXISTS, COUNT or num_rows?

Question

If your only goal is to check if a row exists in php (true or false), what is the best way to do it?

Option 1?

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Answer 1

The EXISTS is faster then SELECT COUNT(*) because the subquery will stop searching when it finds one row. It won't have to find them all and count them. It will return either 0 or 1:

SELECT EXISTS 
       ( SELECT * FROM ... )