if (exists (select name from syscolumns where id = object_id('mm_sample') and name = 'wt_id')) print '该字段已经存在!'; else print '该字段不存在'; go
29 filegrowth=10% 30 ) 31 go 32 use StuDb 33 go 34 if exists(select *from sysobjects where name='StuInfo') 35 drop table StuInfo 36 go 37 create table StuInfo( 38 StuNo int identity(1,1), 39 StuName nvarchar(10) 40 ) 41 go 42 if exists(select *from sysobjects where name='...
Exec(@SQL) --Reset identity column IF EXISTS ( SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE COLUMNPROPERTY( OBJECT_ID( QUOTENAME(table_schema)+ '.' + QUOTENAME(@tableName) ), column_name,'IsIdentity' ) = 1 ) DBCC CHECKIDENT(@tableName,RESEED,0) ...
if exists(select * from Sys.Objects) drop table Player Create table Player ( id int identity(1,1)Constraint PK_Player_Id primary key, 姓名varchar(8)not null, 身份证 char(18) Constraint UQ_Player_身份证 Unique, 性别char(2) Constraint CK_Player_性别 Check(性别='男' or 性别='女'), 身...
import sqlalchemy as db from sqlalchemy import Table, Column, Integer, String, MetaData, ForeignKey, update, exists def dbhandler(): params = urllib.parse.quote_plus(db_string) engine = db.create_engine("mssql+pyodbc:///?odbc_connect={}".format(params)) connection = engine.connect() met...
Check if column exists before dropping with ALTER TABLE DROP COLUMN IF EXISTS It’s likely you don’t want your script to fail and generate an error. To avoid that it will be necessary to check to see if the column exists first.
IF NOT EXISTS (SELECT name FROM sys.databases WHERE name = N'Library') CREATE DATABASE Library; This script creates a new database called Library if it doesn't already exist.The new Library database appears in the list of databases. If you don...
select column from tablename; 检索单个列,如果未排序,返回的顺序可能是数据的添加顺序也可能不是。 select column1,column2 from tablename; 检索多个列 select * from tablename; 检索所有列 ,除非你确实需要表中的每个列,否则最好别用*通配符。虽然使用通配符可能会使你自己省事,但检索不需要的列通常会降低检...
初探Net代码审计原创 漏洞 本文形成于学习Net代码审计的过程中,记录了环境搭建过程中遇到的坑以及跟进代码过程中的一些迷惑并通过查阅相关文章来进行学习。 BA 149375围观·1·32024-04-16 [StartingPoint][Tier2]Markup Web安全 # XXE # Windows #SSH
SET NoCount ON DECLARE @tableName varchar(512) Declare @SQL varchar(2048) SET @tableName='' WHILE EXISTS ( --Find all child tables and those which have no relations SELECT T.table_name FROM INFORMATION_SCHEMA.TABLES T LEFT OUTER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS TC ON T.table_name...