WHERE [NOT] EXISTS (subquery) In some Transact-SQL statements, the subquery can be evaluated as if it were an independent query. Conceptually, the subquery results are substituted into the outer query (although this isn't necessarily how SQL Server actually processes Transact-SQL statements with ...
WHERE word NOT IN (SELECT CommonWords.word FROM dbo.CommonWords); --Using NOT EXISTS SELECT Count(*) FROM dbo.WordsInDracula WHERE NOT EXISTS (SELECT * FROM dbo.CommonWords WHERE CommonWords.word = WordsInDracula.word); 清单1 简而言之,SQL Server优化器以相同的方式处理任一查询,它们也将执行...
syntaxsql複製 EXISTS( subquery ) 引數 subquery 這是受限制的 SELECT 陳述式。 不允許 INTO 關鍵字。 如需詳細資訊,請參閱SELECT (Transact-SQL)中子查詢的相關資訊。 結果類型 布林值 結果值 如果子查詢包含任何資料列,便傳回 TRUE。 範例 A. 在子查詢中使用 NULL,仍會傳回結果集 ...
syntaxsqlCopy EXISTS( subquery ) Arguments subquery Is a restricted SELECT statement. The INTO keyword is not allowed. For more information, see the information about subqueries inSELECT (Transact-SQL). Result Types Boolean Result Values Returns TRUE if a subquery contains any rows. ...
由於SQL Server 查詢最佳化工具通常會選取最好的查詢執行計畫,因此我們建議只有資深的開發人員和資料庫管理員才應該使用提示,並將其當作最後的解決辦法。 適用範圍: DELETE INSERT SELECT UPDATE MERGE Transact-SQL 語法慣例 語法 syntaxsql複製 WITH([ [ , ] ...n ] )::={NOEXPAND|INDEX(<index_value>[ , ...
syntaxsql Copy --Back up a whole database BACKUP DATABASE { database_name | @database_name_var } TO <backup_device> [ ,...n ] [ <MIRROR TO clause> ] [ next-mirror-to ] [ WITH { DIFFERENTIAL | <general_WITH_options> [ ,...n ] } ] [;] --Back up specific files or fi...
WebException: Unable to connect to the remote server System.Net.Sockets.SocketException: An attempt was made to access a socket in a way forbid [Send Mail Task] Error: Either the file "///ServerName//Transfer//Reporting//Completed" does not exist or you do not have permissions to access ...
'DISABLE_OPTIMIZER_ROWGOAL' 让SQL Server 生成计划,它不对包含以下关键字的查询使用行目标修改:- TOP- OPTION (FAST N)- IN- EXISTS此提示名称等效于 跟踪标志 4138。 'DISABLE_PARAMETER_SNIFFING' 指示查询优化器在使用一个或多个参数编译查询时,使用平均数据分布。 此指令让查询计划独立于编译查询时首次使用...
'DISABLE_OPTIMIZER_ROWGOAL' 让SQL Server 生成计划,它不对包含以下关键字的查询使用行目标修改:- TOP- OPTION (FAST N)- IN- EXISTS此提示名称等效于 跟踪标志 4138。 'DISABLE_PARAMETER_SNIFFING' 指示查询优化器在使用一个或多个参数编译查询时,使用平均数据分布。 此指令让查询计划独立于编译查询时首次使用...
SQL Server Transact-SQL Index .NET Framework error occurred during execution of user-defined routine or aggregate "geography" 'IF EXISTS(SELECT COUNT(1))' VS 'IF EXISTS(SELECT 1) ' 'Incorrect syntax near' error while executing dynamic sql 'INSERT EXEC' within a function did not work 'Sort...