本文實(shí)例總結(jié)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(gè)表tb1和tb2
CREATE table tbl1 ( num1 INT NOT NULL);CREATE table tbl2 ( num2 INT NOT NULL);
向兩個(gè)表中插入數(shù)據(jù)：
INSERT INTO tbl1 values(1), (5), (13), (27);INSERT INTO tbl2 values(6), (14), (11), (20);
any some關(guān)鍵字的子查詢
SELECT num1FROM tbl1WHERE num1 > ANY (SELECT num2 FROM tbl2);
all關(guān)鍵字的子查詢
SELECT num1FROM tbl1WHERE num1 > ALL (SELECT num2 FROM tbl2);
exists關(guān)鍵字的子查詢
SELECT * from fruitsWHERE EXISTS(SELECT s_name FROM suppliers WHERE s_id = 107);SELECT * from fruitsWHERE f_price>10.20 AND EXISTS(SELECT s_name FROM suppliers WHERE s_id = 107);SELECT * from fruitsWHERE NOT EXISTS(SELECT s_name FROM suppliers WHERE s_id = 107);
帶in關(guān)鍵字的子查詢
SELECT c_idFROM ordersWHERE o_num IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');SELECT c_idFROM ordersWHERE o_num NOT IN (SELECT o_num FROM orderitems WHERE f_id = 'c0');
帶比較運(yùn)算符的子查詢
SELECT s_id, f_name FROM fruitsWHERE s_id =(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
<>所有非
SELECT s_id, f_name FROM fruitsWHERE s_id <>(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
定義兩個(gè)表tb1和tb2
CREATE table tbl1 ( num1 INT NOT NULL);CREATE table tbl2 ( num2 INT NOT NULL);
向兩個(gè)表中插入數(shù)據(jù)
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(jìn)行比較，只要大于 num2的任何值為符合查詢條件的結(jié)果
SELECT num1FROM tbl1WHERE 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 num1FROM tbl1WHERE num1 > ALL (SELECT num2 FROM tbl2);
【例.55】查詢表suppliers表中是否存在s_id=107的供應(yīng)商，如果存在則查詢fruits表中的記錄
SELECT * from fruitsWHERE 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(yīng)商，如果存在則查詢fruits表中的f_price大于10.20的記錄
SELECT * from fruitsWHERE 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(yīng)商，如果不存在則查詢fruits表中的記錄
SELECT * from fruitsWHERE NOT EXISTS(SELECT s_name FROM suppliers WHERE s_id = 107);
【例.58】在orderitems表中查詢訂購(gòu)f_id為c0的訂單號(hào)，并根據(jù)訂單號(hào)查詢具有訂單號(hào)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(gè)例子語(yǔ)句類(lèi)似，但是在SELECT語(yǔ)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(yīng)商s_id，然后在fruits表中查詢所有該供應(yīng)商提供的水果的種類(lèi)
SELECT s_id, f_name FROM fruitsWHERE 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(yīng)商s_id，然后在fruits表中查詢所有非該供應(yīng)商提供的水果的種類(lèi)，SQL語(yǔ)句如下：
SELECT s_id, f_name FROM fruitsWHERE s_id <>(SELECT s1.s_id from suppliers AS s1 WHERE s1.s_city = 'Tianjin');
希望本文所述對(duì)大家MySQL數(shù)據(jù)庫(kù)計(jì)有所幫助。
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