SELECT 列名称 FROM 表名称
SELECT * FROM 表名称
SELECT DISTINCT Company FROM Orders 去重
SELECT 列名称 FROM 表名称 WHERE 列 运算符 值
| = |
等于 |
| <> |
不等于 |
| > |
大于 |
| < |
小于 |
| >= |
大于等于 |
| <= |
小于等于 |
| BETWEEN |
在某个范围内 |
| LIKE |
搜索某种模式 |
SELECT * FROM Persons WHERE City='Beijing'
SELECT * FROM Persons WHERE FirstName='Thomas' AND LastName='Carter'
SELECT * FROM Persons WHERE FirstName='Thomas' OR LastName='Carter'
SELECT Company, OrderNumber FROM Orders ORDER BY Company
INSERT INTO 表名称 VALUES (值1, 值2,....)
INSERT INTO table_name (列1, 列2,...) VALUES (值1, 值2,....)
UPDATE 表名称 SET 列名称 = 新值 WHERE 列名称 = 某值
UPDATE Person SET FirstName = 'Fred' WHERE LastName = 'Wilson'
UPDATE Person SET Address = 'Zhongshan 23', City = 'Nanjing' WHERE LastName = 'Wilson'
DELETE FROM 表名称 WHERE 列名称 = 值
DELETE FROM Person WHERE LastName = 'Wilson'
DELETE FROM table_name