if exists(select * from sysobjects where name=约束名) alter table 表名 drop constraint 约束名; go alter table 表名 add constraint 约束名 check(约束规则),constraint 约束名 check(约束规则); go 示例: -- 添加一个默认约束 use testss; go if exists(select * from sysobjects where name='check1...
@xml.value('(/b/text())[1]','varchar(10)')--2 对表中的 XML 数据进行解析, 节点下面有多个相同节点的 使用 CROSS APPLY 和 nodes() 方法解析IFOBJECT_ID('tempdb..[#tb]')ISNOTNULLDROPTABLE[#tb]CREATETABLE[#tb]([id]INT,[name]XML)INSERT[#tb]SELECT1,'<r>ab</r>'UNIONALLSELECT2,...
cls # revise directory as desired $dir = 'D:\BCP\'; $bcpFile = $dir + 'myIdentity.bcp'; # Confirm directory exists IF ((Test-Path -Path $dir) -eq 0) { Write-Host "The path $dir does not exist; please create or modify the directory."; RETURN; }; # clear content, will err...
(conn);// Load server properties, if it exists.if(server.LoadProperties()) {string[] slash =newstring[1]; slash[0] =@"\";// If the login is in the form string\string, assume we are// changing the password for a Windows login.if(login.Split(slash, StringSplitOptions.None).Length ...
IF EXISTS (SELECT * FROM tempdb.sys.objects WHERE [name] like '#WaitResources%') DROP TABLE #WaitResources; CREATE TABLE #WaitResources (session_id INT, wait_type NVARCHAR(1000), wait_duration_ms INT, resource_description sysname NULL, db_name ...
IF EXISTS(SELECT * FROM sys.server_event_sessions WHERE name='FindBlockers') DROP EVENT SESSION FindBlockers ON SERVER GO -- Use dynamic SQL to create the event session and allow creating a -- predicate on the AdventureWorks database id. -- DECLARE @dbid int SELECT @dbid = db_id('...
IF EXISTS (SELECTnameFROMsys.indexesWHEREname= N'FIBillOfMaterialsWithComponentID'ANDobject_id = OBJECT_ID(N'Production.BillOfMaterials'))DROPINDEXFIBillOfMaterialsWithComponentIDONProduction.BillOfMaterials; GOCREATENONCLUSTEREDINDEX[FIBillOfMaterialsWithComponentID]ONProduction.BillOfMaterials(ComponentID,...
Private Function CheckEntry1() Dim sSQL As String Dim x As String sSQL = "EXISTS(SELECT * FROM tblCloud.IDCloud WHERE tblCloud.[IDCloud] = '000000001');" x = DoCmd.RunSQL(sSQL) MsgBox (x) End Function So I need to be able to look up whether a value exists in a fiel...
–value() 方法从 XML 中检索 rogue 属性值。然后将该值分配给 int 变量。 SELECT @x.value(’(/root/rogue/@id)[1]’,‘int’) –解析 hobo 中属性 id 为2 的所有元素值 SELECT @x.value(’(/root/rogue[2]/hobo/@id)[1]’,‘int’) ...
MAXDOP <integer_value> 适用于:SQL Server(从 SQL Server 2008 (10.0.x) 开始)和 Azure SQL 数据库。 替代sp_configure的“最大并行度”配置选项。 还会替代指定此选项的查询 Resource Governor。 查询MAXDOP提示可以超出配置sp_configure的值。 如果MAXDOP超出使用资源调控器配置的值,则数据库引擎使用 ALTER WORK...