我有两张桌子:玩具和游戏.
+--------------------+------------------+
| Field | Type |
+--------------------+------------------+
| toy_id | int(10) unsigned |
| little_kid_id | int(10) unsigned |
+--------------------+------------------+
+--------------------+------------------+
| Field | Type |
+--------------------+------------------+
| game_id | int(10) unsigned |
| little_kid1 | int(10) unsigned |
| little_kid2 | int(10) unsigned |
| little_kid3 | int(10) unsigned |
+--------------------+------------------+
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一个小孩可以有多个玩具.一个小孩可以同时参加多个游戏.
我想要一个查询,它会给我一个little_kid所涉及的玩具+游戏的总数.
基本上,我想要这两个查询的总和:
SELECT COUNT(*) FROM Toys WHERE little_kid_id = 900; SELECT COUNT(*) from Games WHERE little_kid1 = 900 OR little_kid2 = 900 OR little_kid3 = 900; …