因為這些資料表是在 tempdb 中建立的,所以存取它們的查詢是否要重新編譯,取決於 AUTO_UPDATE_STATISTICS 中tempdb 的設定。 在SQL Server 2005 之前,即使此設定為 OFF,還是會繼續根據 DML 觸發程序插入和刪除資料表的基數變更來重新編譯查詢。參數和執行計畫的重複使用參數的使用,包括 ADO、
CASEcan be used in any statement or clause that allows a valid expression. For example, you can useCASEin statements such as SELECT, UPDATE, DELETE and SET, and in clauses such as, IN, WHERE, ORDER BY, and HAVING. Transact-SQL syntax...
Performing anUPDATEusing a secondarySELECTstatementcan be accomplished in one of two ways, primarily depending upon which version of SQL Server you are using. 使用辅助语句来执行UPDATE,可以通过以下两种方法之一来完成,这主要取决于所使用的SQL Server版本。 We’llbriefly exploreboth options so you can fi...
需要明确的 CTE 引用,因为 CTE 没有对象 ID,SQL Server 使用该 ID 来识别对象与其别名之间的隐式关系。 如果没有这一关系,查询计划可能会产生意外的联接行为和意外的查询结果。 以下示例演示在 CTE 是更新操作的目标对象时指定 CTE 的正确和不正确的方法。 SQL 复制 USE tempdb; GO -- UPDATE statement ...
CASEcan be used in any statement or clause that allows a valid expression. For example, you can useCASEin statements such as SELECT, UPDATE, DELETE and SET, and in clauses such as, IN, WHERE, ORDER BY, and HAVING. Transact-SQL syntax...
SQL Server日常维护常用的一些脚本整理。 1.sql server开启clr权限: exec sp_configure'clr enabled',1GO RECONFIGURE GO ALTER DATABASE HWMESTC SET TRUSTWORTHY ON ALTER AUTHORIZATION ON Database::HWMESTC TO sa; 2.查询数据库大小 Exec sp_spaceusedselectname, convert(float,size) * (8192.0/1024.0)/10...
, head.wait_type, head.wait_time, head.wait_resource, head.statement_start_offset, head.statement_end_offset , head.plan_handle, head.sql_handle, head.most_recent_sql_handle,0AS[Level]FROMcteHeadASheadWHERE(head.blocking_session_idISNULLORhead.blocking_session_id =0)ANDhead.session_idIN(...
For example, in the UPDATE statement in the following script, both rows in Table1 meet the qualifications of the FROM clause in the UPDATE statement; but it is undefined which row from Table1 is used to update the row in Table2. SQL Copy USE AdventureWorks2022; GO IF OBJECT_ID ('dbo...
USE tempdb; GO -- UPDATE statement with CTE references that are correctly matched. DECLARE @x TABLE (ID INT, Value INT); DECLARE @y TABLE (ID INT, Value INT); INSERT @x VALUES (1, 10), (2, 20); INSERT @y VALUES (1, 100),(2, 200); WITH cte AS (SELECT * FROM @x) UPD...
AlterRemoteServiceBindingStatement AlterResourceGovernorCommandType AlterResourceGovernorStatement AlterResourcePoolStatement AlterRoleAction AlterRoleStatement AlterRouteStatement AlterSchemaStatement AlterSearchPropertyListStatement AlterSecurityPolicyStatement AlterSequenceStatement AlterServerAuditSpecificationStatement ...