V = 视图 X = 扩展存储过程*/--数据库IFexists(SELECT1fromsys. sysdatabaseswherename=dbname)begindropdatabasedbnameend--表IFexists(SELECT1fromsys. sysobjectswhereid=object_id(N'tbname')ANDOBJECTPROPERTY(id, N'IsUserTable')=1)BEGINdropTABLEtbnameEND--存储过程IFexists(SELECT1fromsys. sysobjectsw...
USEmasterGOIFEXISTS(SELECT*FROMsysdatabasesWHEREname='people')DROPDATABASEpeople 注:EXISTS(查询语句)用来检测某个查询是否存在。 二、创建和删除表 1、创建表的语法如下: CREATETABLE表名 ( 字段1 数据类型 列的特征, 字段2 数据类型 列的特征, ... ) 示例: 需求:创建学员信息表peoInfo。 USEpeopleGOCREA...
代码如下: --账号表ifexists(select*fromsysobjectswherename='Account')droptableAccountgocreatetableAccount(AccountIdintidentity(10001,1)primarykey,--账号编号AccountNamevarchar(20)notnull,--账号名称AccountContentnvarchar(500)notnull,--账号简介originalityintnotnull,--原创数TypeIdintreferencesAccountType(TypeId...
这次介绍一下T-SQL中“Not IN” 和“Not Exists”的优化。 Not IN 和 Not Exists 命令 : 有些情况下,需要select/update/delete 操作孤立数据。...孤立数据:不存在主表中而存在其关联表中。操作这样的数据,一般第一反应是利用“Not in” 或“Not Exi...
Use tempDB IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo]. 05 [ProductNew]') AND type in (N'U')) DROP TABLE [dbo].[ProductNew] -- STEP 2: 建立訂單資料表 06 CREATE TABLE dbo.ProductNew( ProductID int primary key, FilmName nvarchar(30), direct nvarcha...
if exists(select * from sysobjects where name='Teacher') drop table Teacher go create table Teacher ( -- TeacherId int primary key, --讲师编号,主键 TeacherId int identity(100,1) primary key,--自增主键用identity(基数,增量) LoginAccount varchar(50) not null,--登录帐号 ...
-- 1 多语句内联函数(获取级联子节点)定义 DROP FUNCTION IF EXISTS dbo.func_GetChildtree; GO CREATE FUNCTION dbo.func_GetChildtree (@mgrid AS INT, @maxlevels AS INT = NULL) RETURNS @Tree TABLE -- 定义表变量以接收处理结果 ( empid INT NOT NULL PRIMARY KEY, mgrid INT NULL, empname VARCH...
@stmt = N'SELECTc.LastName, c.FirstName, e.TitleFROMHumanResources.EmployeeASeWITH(NOLOCK,INDEX(PK_Employee_EmployeeID))JOINPerson.ContactAScONe.ContactID = c.ContactIDWHEREe.ManagerID =2;', @type = N'SQL', @module_or_batch = NULL, @params = NULL, @hints = N'OPTION (TABLE HINT ...
@description = 'CreateTableTest'; -- Add job step for create table EXEC jobs.sp_add_jobstep @job_name = 'CreateTableTest', @command = N'IFNOTEXISTS(SELECT*FROMsys.tablesWHEREobject_id = object_id(''Test''))CREATETABLE[dbo].[Test]([TestId] [int]NOTNULL);', @target_group_name =...
DROP TABLE IF EXISTS [dbo].[fact_sale]; --Create the fact_sale table. CREATE TABLE [dbo].[fact_sale] ( [SaleKey] [bigint] NULL, [CityKey] [int] NULL, [CustomerKey] [int] NULL, [BillToCustomerKey] [int] NULL, [StockItemKey] [int] NULL, [InvoiceDateKey] [datetime2](6) ...