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Specifies a temporary named result set, known as a common table expression (CTE). This is derived from a simple query and defined within the execution scope of a single SELECT, INSERT, UPDATE, MERGE, or DELETE statement. This clause can also be used in a CREATE VIEW statement as part of...
Transact-SQL syntax conventionsSyntaxsyntaxsql העתק [ WITH <common_table_expression> [ ,...n ] ] <common_table_expression>::= expression_name [ ( column_name [ ,...n ] ) ] AS ( CTE_query_definition ) הערה To view Transact-SQL syntax for SQL Server 2014 (...
3. 如果CTE的表达式名称与某个数据表或视图重名,则紧跟在该CTE后面的SQL语句使用的仍然是CTE,当然,后面的SQL语句使用的就是数据表或视图了,如下面的SQL语句所示: -- table1是一个实际存在的表 with table1 as ( select * from persons where age < 30 ) select * from table1 -- 使用了名为table1的公...
n ] ] <common_table_expression>::= expression_name [ ( column_name [ ,...n ] ) ] AS ( CTE_query_definition ) 参数 expression_name 是公用表表达式的有效标识符。 expression_name 须不同于在同一 WITH <common_table_expression> 子句中定义的任何其他公用表表达式的名称,但可以与基表或基视图的...
Convenzioni relative alla sintassi Transact-SQLSintassisyntaxsql Copia [ WITH <common_table_expression> [ ,...n ] ] <common_table_expression>::= expression_name [ ( column_name [ ,...n ] ) ] AS ( CTE_query_definition ) Argomentiexpression_name...
公用表表达式(Common Table Expression)是SQL Server2005版本的引入的一个特性。CTE可以看组是一个临时的结果集,可以再接下来来的一个 SELECT,INSERT,UPDATE,DELETE,MERGE语句中多次引用。使用公用表达式CTE可以让语句更加清晰简练。与公用表达式作用类 似的还有临时表和表变量。下面给出三种方法的对比。
更多使用详细介绍与使用可参考:https://docs.microsoft.com/zh-cn/sql/t-sql/queries/with-common-table-expression-transact-sql?view=sql-server-ver15 一路走来数个年头,感谢RDIFramework.NET框架的支持者与使用者,大家可以通过下面的地址了解详情。
A common table expression (CTE) can be thought of as a temporary result set that is defined within the execution scope of a single SELECT, INSERT, UPDATE, DELETE, or CREATE VIEW statement. A CTE is similar to a derived table in that it is not stored as an object and lasts only for ...
Transact-SQL-Referenz für die Verwendung von allgemeinen Tabellenausdrücken (Common Table Expressions, CTE) in Abfragen