Re: How to replace in syntax when calling stored procedure?

[Devart Team]

Change '%y%m%d' format to '%Y%m%d'. And remove GROUP BY clause, because query with GROUP BY clause can return more then one row.

CREATE FUNCTION NumOfTests(yr  VARCHAR(4), mth VARCHAR(2))
RETURNS INT(11)
BEGIN
  DECLARE number INT DEFAULT 0;

  SELECT
    COUNT(DISTINCT SN) INTO number
  FROM
    tester
  WHERE
    Date > STR_TO_DATE(CONCAT(yr, mth, '01'), '%Y%m%d') AND Date < STR_TO_DATE(CONCAT(yr, mth, '01'), '%Y%m%d') + INTERVAL 1 MONTH;

  RETURN (number);
END

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