COUNT function counts the number of rows retrieved by a SELECT statement. The return value is of type BIGINT. The COUNT(expr) function count the number of non-NULL values of expr in the rows retrieved by a SELECT statement. SELECT COUNT(expr) FROM tbl; In contrast, COUNT(*) is different in that it returns a count of the […]
A SELECT statement with COUNT returns the number of rows retrieved by the SELECT statement (see mysql select count). For performance reasons, the desired result is to limit that count. Including a LIMIT clause in the SELECT statement will not work since it only restricts the number of rows returned, which is always one. The […]
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