1. 程式人生 > >SQL Server(第一章) 創建表 刪除表 創建主鍵約束、唯一約束、外鍵約束、CHECK約束、默認約束

SQL Server(第一章) 創建表 刪除表 創建主鍵約束、唯一約束、外鍵約束、CHECK約束、默認約束

tsql mil null employee alter bold soft arc 刪除表


1.Employees員工表
/**
創建Employees員工表
**/
USE TSQL2012
IF OBJECT_ID(dbo.Employees,U) IS NOT NULL
DROP TABLE dbo.Employees

CREATE TABLE dbo.Employees
(
    empid    INT    NOT NULL,
    firstname    VARCHAR(30)    NOT NULL,
    lastname    VARCHAR(30)    NOT NULL,
    hiredate    DATE    NOT NULL,
    mgrid    
INT NULL, ssn VARCHAR(20) NOT NULL, salary MONEY NOT NULL ) /** 添加主鍵約束 **/ ALTER TABLE dbo.Employees ADD CONSTRAINT PK_Employees PRIMARY KEY(empid); /** 添加唯一約束 **/ ALTER TABLE dbo.Employees ADD CONSTRAINT UNQ_Employees_ssn UNIQUE(ssn); /** 添加外鍵約束 **/ ALTER TABLE dbo.Employees ADD
CONSTRAINT FK_Employees_Employees FOREIGN KEY(mgrid) REFERENCES dbo.Employees(empid); /** 添加CHECK約束 **/ ALTER TABLE dbo.Employees ADD CONSTRAINT CHK_Employees_salary CHECK(salary>0.00) /** 刪除CHECK約束 **/ ALTER TABLE dbo.Employees DROP CONSTRAINT CHK_Employees_salary

2.Orders訂單表

/**
    創建Orders訂單表
**/
USE TSQL2012 IF OBJECT_ID(dbo.Orders,U) IS NOT NULL DROP TABLE dbo.Orders; CREATE TABLE dbo.Orders ( orderid INT NOT NULL, empid INT NOT NULL, custid VARCHAR(10) NOT NULL, orderts DATETIME2 NOT NULL, qty INT NOT NULL, CONSTRAINT PK_Orders PRIMARY KEY(orderid) ); /** 添加主鍵約束 **/ ALTER TABLE dbo.Orders ADD CONSTRAINT FK_Orders_Employees FOREIGN KEY(empid) REFERENCES dbo.Employees(empid); /** 添加默認約束 **/ ALTER TABLE dbo.Orders ADD CONSTRAINT DFT_Orders_orderts DEFAULT(SYSDATETIME()) FOR orderts; /** 刪除CHECK約束 **/ ALTER TABLE dbo.Employees DROP CONSTRAINT DFT_Orders_orderts

SQL Server(第一章) 創建表 刪除表 創建主鍵約束、唯一約束、外鍵約束、CHECK約束、默認約束