如何在 MySQL 聯結中實現表之間的交集(INTERSECTION)?
實際上,INTERSECTION 只是對所有列進行的內聯接。我們以兩個表的簡單示例來說明,資料如下 −
mysql> Select * from value1; +------+------+ | i | j | +------+------+ | 1 | 1 | | 2 | 2 | +------+------+ 2 rows in set (0.00 sec) mysql> Select * from value2; +------+------+ | i | j | +------+------+ | 1 | 1 | | 3 | 3 | +------+------+ 2 rows in set (0.00 sec)
現在,以下查詢將在這些表之間執行 INTERSECTION −
mysql> Select * from value1 join value2 using(i,j); +------+------+ | i | j | +------+------+ | 1 | 1 | +------+------+ 1 row in set (0.08 sec)
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