本文實例總結了MySQL子查詢操作。分享給大家供大家參考，具體如下：
定義兩個表tb1和tb2
CREATE table tbl1 ( num1 INT NOT NULL); CREATE table tbl2 ( num2 INT NOT NULL);
向兩個表中插入數據：
INSERT INTO tbl1 values(1), (5), (13), (27); INSERT INTO tbl2 values(6), (14), (11), (20);
any some關鍵字的子查詢
SELECT num1 FROM tbl1 WHERE num1 > ANY (SELECT num2 FROM tbl2);
all關鍵字的子查詢
SELECT num1 FROM tbl1 WHERE num1 > ALL (SELECT num2 FROM tbl2);
exists關鍵字的子查詢
SELECT * from fruits WHERE EXISTS (SELECT s_name FROM suppliers WHERE s_id = 107); SELECT * from fruits WHERE f_price>10.20 AND EXISTS (SELECT s_name FROM suppliers WHERE s_id = 107); SELECT * from fruits WHERE NOT EXISTS (SELECT s_name FROM suppliers WHERE s_id = 107);
帶in關鍵字的子查詢
SELECT c_id FROM orders WHERE o_num IN (SELECT o_num FROM orderitems WHERE f_id = 'c0'); SELECT c_id FROM orders WHERE o_num NOT IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');
帶比較運算符的子查詢
SELECT s_id, f_name FROM fruits WHERE s_id = (SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
<>所有非
SELECT s_id, f_name FROM fruits WHERE s_id <> (SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
定義兩個表tb1和tb2
CREATE table tbl1 ( num1 INT NOT NULL); CREATE table tbl2 ( num2 INT NOT NULL);
向兩個表中插入數據
INSERT INTO tbl1 values(1), (5), (13), (27); INSERT INTO tbl2 values(6), (14), (11), (20);
【例.53】返回tbl2表的所有 num2 列，然后將 tbl1 中的 num1 的值與之進行比較，只要大于 num2的任何值為符合查詢條件的結果
SELECT num1 FROM tbl1 WHERE num1 > ANY (SELECT num2 FROM tbl2);
【例.54】返回tbl1表的中比tbl2表num2 列所有值都大的值
SELECT num1 FROM tbl1 WHERE num1 > ALL (SELECT num2 FROM tbl2);
【例.55】查詢表suppliers表中是否存在s_id=107的供應商，如果存在則查詢fruits表中的記錄
SELECT * from fruits WHERE EXISTS (SELECT s_name FROM suppliers WHERE s_id = 107);
【例.56】查詢表suppliers表中是否存在s_id=107的供應商，如果存在則查詢fruits表中的f_price大于10.20的記錄
SELECT * from fruits WHERE f_price>10.20 AND EXISTS (SELECT s_name FROM suppliers WHERE s_id = 107);
【例.57】查詢表suppliers表中是否存在s_id=107的供應商，如果不存在則查詢fruits表中的記錄
SELECT * from fruits WHERE NOT EXISTS (SELECT s_name FROM suppliers WHERE s_id = 107);
【例.58】在orderitems表中查詢訂購f_id為c0的訂單號，并根據訂單號查詢具有訂單號的客戶c_id
SELECT c_id FROM orders WHERE o_num IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');
【例.59】與前一個例子語句類似，但是在SELECT語句中使用NOT IN操作符
SELECT c_id FROM orders WHERE o_num NOT IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');
【例.60】在suppliers表中查詢s_city等于Tianjin的供應商s_id，然后在fruits表中查詢所有該供應商提供的水果的種類
SELECT s_id, f_name FROM fruits WHERE s_id = (SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
【例.61】在suppliers表中查詢s_city等于Tianjin的供應商s_id，然后在fruits表中查詢所有非該供應商提供的水果的種類，SQL語句如下：
SELECT s_id, f_name FROM fruits WHERE s_id <> (SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
希望本文所述對大家MySQL數據庫計有所幫助。
