我來到SQL查詢運算符所在的位置。 < =>運算符是什麼意思?<=>運算符是什麼意思,sql?
SELECT STR_ID, TEX_TEXT AS STR_DES_TEXT, IF(EXISTS(SELECT * FROM SEARCH_TREE AS SEARCH_TREE2 WHERE SEARCH_TREE2.STR_ID_PARENT <=> SEARCH_TREE.STR_ID LIMIT 1), 1, 0) AS DESCENDANTS FROM SEARCH_TREE
此sql屬於MySQL類型。
非常感謝。 –