SQL SERVER 2000新增功能介紹1
2024-08-31 00:48:30
供稿:網友
 
建立用戶自定義函數,可以自由的在一個transaction sql 中直接使用,就像一個系統函數一樣在你的查詢語句中
直接使用。
create function
語法
create  function [ owner_name. ] function_name 
    ( [ { @parameter_name [as] scalar_parameter_data_type [ = default ] } [ ,...n ] ] ) 
returns scalar_return_data_type
[ with < function_option> [ [,] ...n] ] 
[ as ]
begin 
    function_body 
    return scalar_expression
end
inline table-valued functions
create function [ owner_name. ] function_name 
    ( [ { @parameter_name [as] scalar_parameter_data_type [ = default ] } [ ,...n ] ] ) 
returns table 
[ with < function_option > [ [,] ...n ] ] 
[ as ] 
return [ ( ] select-stmt [ ) ] 
multi-statement table-valued functions
create function [ owner_name. ] function_name 
    ( [ { @parameter_name [as] scalar_parameter_data_type [ = default ] } [ ,...n ] ] ) 
returns @return_variable table < table_type_definition > 
[ with < function_option > [ [,] ...n ] ] 
[ as ] 
begin 
    function_body 
    return
end
< function_option > ::= 
    { encryption | schemabinding }
< table_type_definition > :: = 
    ( { column_definition | table_constraint } [ ,...n ] ) 
示例
--創建函數
create  function getvalue()
returns int
as 
begin
return (select convert(int,value) as value from test where  [name]='test')
end
go
select * from test2 where value=dbo.getvalue()
go
create  function gettabletest(@t1 datetime,@t2 datetime)
returns table 
as
 return( select t1.field1 ,t2.field1,t2.qty,t3.field1,t3.field1
 from table1 t1 inner join  table2 t2 on t1.id=t2.id inner join table3 t3 on t2.jid=t3.jid where t1.date>[email protected] and t1.date<@t2)
go
select * from dbo.gettabletest('1999/1/1','2001/2/1')