Syntax for Transact-SQL scalar functions. syntaxsql复制 CREATE[ORALTER]FUNCTION[schema_name. ]function_name( [ { @parameter_name[AS] [type_schema_name. ]parameter_data_type[NULL] [ = default ] [READONLY] } [ , ...n ] ] )RETURNSreturn_data_type[WITH<function_option>[ , ...n ] ...
Syntax for Transact-SQL scalar functions. syntaxsql 複製 CREATE [ OR ALTER ] FUNCTION [ schema_name. ] function_name ( [ { @parameter_name [ AS ] [ type_schema_name. ] parameter_data_type [ NULL ] [ = default ] [ READONLY ] } [ , ...n ] ] ) RETURNS return_data_t...
Syntax for Transact-SQL scalar functions. syntaxsql Copy CREATE [ OR ALTER ] FUNCTION [ schema_name. ] function_name ( [ { @parameter_name [ AS ] [ type_schema_name. ] parameter_data_type [ NULL ] [ = default ] [ READONLY ] } [ , ...n ] ] ) RETURNS return_data_type [ ...
在純量函數中,function_body 是一系列的 Transact-SQL 陳述式,這些陳述式會一起評估為純量值。 在多重陳述式資料表值函式中,function_body 是 Transact-SQL 陳述式序列,這些陳述式會擴展 TABLE 傳回變數。 scalar_expression 指定純量函數傳回的純量值。 TABLE 指定資料表值函式的傳回值是資料表。只有常數和...
用户定义函数用 ALTER FUNCTION 修改，用 DROP FUNCTION 除去。 语法 标量函数 CREATE FUNCTION [ owner_name.] function_name ( [ { @parameter_name [AS] scalar_parameter_data_type [ = default ] } [ ,...n ] ] ) RETURNS scalar_return_data_type [ WITH < function_option> [ [,] ...n] ]...
スカラー関数の function_body は、総合してスカラー値と評価される一連の Transact-SQL ステートメントです。 scalar_expression スカラー関数が返すスカラー値を指定します。 select_stmt インライン テーブル値関数の戻り値を定義する単一 SELECT のステートメントです。 インライン テーブル...
Scalar function examples Table-valued function examples Show 2 more Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) This article describes how to create a user-defined function (UDF) in SQL Server by using Transact-SQL....
Avoid using scalar functions in SELECT statements that return many rows of data. Because the scalar function must be applied to every row, the resulting behavior is like row-based processing and degrades performance. Avoid the use of SELECT *. Instead, specify the required column names. This ...
Only a constant value, such as a character string; a scalar function (either a system, user-defined, or CLR function); or NULL can be used as a default. To maintain compatibility with earlier versions of SQL Server, a constraint name can be assigned to a DEFAULT. constant_expression A ...
This CREATE FUNCTION (external scalar) statement defines an external scalar function at the current server. A user-defined external scalar function returns a single value each time it is invoked. Invocation This statement can be embedded in an application program, or issued interactively. It is an...