一.增刪改


原表

1.數(shù)據(jù)插入——INSERT INTO
(1)在表中插入自己寫的行
SELECT * FROM prod_info2;
INSERT INTO prod_info2
VALUES('T00001', '測(cè)試商品', 'test', 'test', 'test', 16, 20, 'NJ0001');
SELECT * FROM prod_info2 ORDER BY prod_id DESC;
INSERT INTO prod_info2 (prod_id, prod_name, brand, type)
VALUES('T00002', '測(cè)試商品', 'test', 'test');
INSERT INTO prod_info2 (prod_id, prod_name, type, brand)
VALUES('T00003', '測(cè)試商品', 'type', 'brand');
SELECT * FROM prod_info2 ORDER BY prod_id DESC;

(2)在表中插入另一個(gè)表中的一行
插入整行
INSERT INTO prod_info2
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type, p.class, p.cost, p.sale_price, p.supplier_id
FROM prod_info AS p
WHERE p.prod_id = '10001';

插入部分行
INSERT INTO prod_info2(prod_id, prod_name, brand, type)
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type
FROM prod_info AS p
WHERE p.prod_id = '10002';

(3)在表中插入了一個(gè)表中的多行
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type, p.class, p.cost, p.sale_price, p.supplier_id
FROM prod_info AS p
WHERE p.prod_id LIKE '2000_';
INSERT INTO prod_info2
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type, p.class, p.cost, p.sale_price, p.supplier_id
FROM prod_info AS p
WHERE p.prod_id LIKE '2000_';

2.數(shù)據(jù)更新——UPDATE

(1)無(wú)過(guò)濾修改列
UPDATE prod_info2
SET class = '日用品';

(2)有過(guò)濾條件修改列
UPDATE prod_info2
SET class = '零食'
WHERE prod_id LIKE 'T2%';

UPDATE prod_info2
SET class = '飲料'
WHERE prod_id LIKE '3%';

WHERE prod_info2
SET sale_price = sale_price * 0.9
WHERE prod_name = '抽紙' OR class = '飲料';
UPDAT prod_info2
SET sale_price = sale_price * 0.9, cost = cost * 0.9;
(3)通過(guò)關(guān)聯(lián)方式對(duì)表進(jìn)行更新
SELECT p2.*, p.*
FROM prod_info2 AS p2 INNER JOIN prod_info AS p
WHERE p2.prod_name = p.prod_name
AND p2.brand = p.brand
AND p2.type = p.type;
UPDATE prod_info2 AS p2
INNER JOIN prod_info AS p
SET p2.cost = p.sale_price
WHERE p2.prod_name = p.prod_name
AND p2.brand = p.brand
AND p2.type = p.type;
SELECT * FROM prod_info2 ORDER BY prod_id DESC;

3.數(shù)據(jù)刪除——DELETE

(1)刪除
SELECT * FROM prod_info2 AS p2 WHERE class = '測(cè)試商品';
DELETE FROM prod_info2 WHERE prod_name = '測(cè)試商品';

二.今日代碼
SELECT * FROM prod_info2;
INSERT INTO prod_info2
VALUES('T00001', '測(cè)試商品', 'test', 'test', 'test', 16, 20, 'NJ0001');
SELECT * FROM prod_info2 ORDER BY prod_id DESC;
INSERT INTO prod_info2 (prod_id, prod_name, brand, type)
VALUES('T00002', '測(cè)試商品', 'test', 'test');
INSERT INTO prod_info2 (prod_id, prod_name, type, brand)
VALUES('T00003', '測(cè)試商品', 'type', 'brand');
SELECT * FROM prod_info2 ORDER BY prod_id DESC;
SELECT * FROM prod_info AS p WHERE p.prod_id = '10001';
INSERT INTO prod_info2
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type, p.class, p.cost, p.sale_price, p.supplier_id
FROM prod_info AS p
WHERE p.prod_id = '10001';
INSERT INTO prod_info2(prod_id, prod_name, brand, type)
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type
FROM prod_info AS p
WHERE p.prod_id = '10002';
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type, p.class, p.cost, p.sale_price, p.supplier_id
FROM prod_info AS p
WHERE p.prod_id LIKE '2000_';
INSERT INTO prod_info2
SELECT CONCAT('T', p.prod_id), p.prod_name, p.brand, p.type, p.class, p.cost, p.sale_price, p.supplier_id
FROM prod_info AS p
WHERE p.prod_id LIKE '2000_';
SELECT * FROM prod_info2 ORDER BY prod_id DESC;
UPDATE prod_info2
SET class = '日用品';
UPDATE prod_info2
SET class = '零食'
WHERE prod_id LIKE 'T2%';
UPDATE prod_info2
SET class = '飲料'
WHERE prod_id LIKE '3%';
WHERE prod_info2
SET sale_price = sale_price / 0.9
WHERE prod_name = '抽紙' OR class = '飲料';
UPDATE prod_info2
SET sale_price = sale_price * 0.9, cost = cost * 0.9;
SELECT p2.*, p.*
FROM prod_info2 AS p2 INNER JOIN prod_info AS p
WHERE p2.prod_name = p.prod_name
AND p2.brand = p.brand
AND p2.type = p.type;
UPDATE prod_info2 AS p2
INNER JOIN prod_info AS p
SET p2.cost = p.sale_price
WHERE p2.prod_name = p.prod_name
AND p2.brand = p.brand
AND p2.type = p.type;
SELECT * FROM prod_info2 ORDER BY prod_id DESC;
SELECT * FROM prod_info2 AS p2 WHERE class = '測(cè)試商品';
DELETE FROM prod_info2 WHERE prod_name = '測(cè)試商品';
三.課后作業(yè)
Q1:寫出插入語(yǔ)句的兩種語(yǔ)句結(jié)構(gòu),并分析其使用場(chǎng)景。
答:INSERET INTO<表名>VALUES(<插入值1>,<插入值2>,......)
第一種方法較為簡(jiǎn)單,僅適用于整行插入,且要求表結(jié)構(gòu)固定。
INSERT INTO<表名>(<插入字段1>,<插入字段2>,......)VALUES(<插入值>,<插入值>,......)
第二種方法更為具體,既可以用于整行插入也可以用于部分行插入,且插入順序可以進(jìn)行自定義。并且,即使表后續(xù)結(jié)構(gòu)發(fā)生修改,只要插入字段依然存在,則該語(yǔ)句依舊有效。
Q2:請(qǐng)寫出更新表的語(yǔ)句結(jié)構(gòu)(多列),以及更新操作的注意事項(xiàng)。
答:
UPDATE<表名>
SET<列名1> = 值1, <列名2> = 值2
WHERE<過(guò)濾條件>;
一定要注意過(guò)濾條件的檢查。
Q3:分別寫出以下語(yǔ)句。
1、向 milk_tea 表中插入一個(gè)完整的行:(9,測(cè)試商品 1,100g,2019-01-01,12,13,20)
INSERT INTO milk_tea
VALUES(9, '測(cè)試商品1', '100g', 20190101, 12, 13, 20);
2、向 milk_tea 表中插入以下數(shù)據(jù):prod_id = 10,pro_date = “2018-01-01”,prod_name = “測(cè)試商品 2”
INSERT INTO milk_tea (prod_id, pro_date, prod_name)
VALUES (10, 20180101, '測(cè)試商品2');
3、從 milk_tea 表中找到‘棒棒糖’的行,修改 prod_id 為 11 后重新插入 milk_tea 表
UPDATE milk_tea
SET prod_id = 11
WHERE prod_name = '棒棒糖';
4、修改 prod_id 為 11 的行數(shù)據(jù),將 prod_name 修改為“測(cè)試商品 3”
UPDATE milk_tea
SET prod_name = '測(cè)試商品3'
WHERE prod_id = 11;
5、刪除 prod_id 為 9、10、11 的行。
DELETE
FROM milk_tea
WHERE prod_id IN (9, 10, 11);