Question

SQL 存储过程中参数怎么使用

Answer 1

参数定义
单个参数
1>
CREATE
PROCEDURE
HelloWorld1
2>
@UserName
VARCHAR(10)
3>
AS
4>
BEGIN
5>
PRINT
'Hello'
+
@UserName
+
'!';
6>
END;
7>
go
1>
DECLARE
@RC
int;
2>
EXECUTE
@RC
=
HelloWorld1
'Edward'
;
3>
PRINT
@RC;
4>
go
HelloEdward!
0
IN、OUT、IN
OUT
注：
SQL
Server
的
OUTPUT
需要写在变量数据类型后面。
SQL
Server
没有
IN
OUT
关键字
OUTPUT
已经相当于
IN
OUT
了。
1>
CREATE
PROCEDURE
HelloWorld2
2>
@UserName
VARCHAR(10),
3>
@OutVal
VARCHAR(10)
OUTPUT,
4>
@InoutVal
VARCHAR(10)
OUTPUT
5>
AS
6>
BEGIN
7>
PRINT
'Hello
'
+
@UserName
+
@InoutVal
+
'!';
8>
SET
@OutVal
=
'A';
9>
SET
@InoutVal
=
'B';
10>
END;
11>
go
1>
2>
DECLARE
@RC
int,
@OutVal
VARCHAR(10),
@InoutVal
VARCHAR(10);
3>
BEGIN
4>
SET
@InoutVal
=
'~Hi~';
5>
EXECUTE
@RC
=
HelloWorld2
'Edward',
@OutVal
OUTPUT,
@InoutVal
OUTPUT;
6>
PRINT
@RC;
7>
PRINT
'@OutVal='
+
@OutVal;
8>
PRINT
'@InoutVal='
+
@InoutVal;
9>
END
10>
go
Hello
Edward~Hi~!
0
@OutVal=A
@InoutVal=B
参数的默认值
1>
CREATE
PROCEDURE
HelloWorld3
2>
@UserName
VARCHAR(10),
3>
@Val1
VARCHAR(20)
=
'
Good
Moning,',
4>
@Val2
VARCHAR(20)
=
'
Nice
to
Meet
you'
5>
AS
6>
BEGIN
7>
PRINT
'Hello
'
+
@UserName
+
@Val1
+
@Val2
+
'!';
8>
END;
9>
go
1>
2>
DECLARE
@RC
int;
3>
BEGIN
4>
EXECUTE
@RC
=
HelloWorld3
'Edward';
5>
PRINT
@RC;
6>
EXECUTE
@RC
=
HelloWorld3
'Edward',
'
Good
Night,';
7>
PRINT
@RC;
8>
EXECUTE
@RC
=
HelloWorld3
'Edward',
'
Good
Night,',
'
Bye';
9>
PRINT
@RC;
10>
END
11>
go
Hello
Edward
Good
Moning,
Nice
to
Meet
you!
0
Hello
Edward
Good
Night,
Nice
to
Meet
you!
0
Hello
Edward
Good
Night,
Bye!
0
指定参数名称调用
此部分使用
“参数默认值”那一小节的存储过程。
用于说明当最后2个参数是有默认的时候，如何跳过中间那个。
1>
DECLARE
@RC
int;
2>
BEGIN
3>
EXECUTE
@RC
=
HelloWorld3
'Edward';
4>
PRINT
@RC;
5>
EXECUTE
@RC
=
HelloWorld3
'Edward',
@Val1='
Good
Night,';
6>
PRINT
@RC;
7>
EXECUTE
@RC
=
HelloWorld3
'Edward',
@Val1='
Good
Night,',
@Val2='
Bye';
8>
PRINT
@RC;
9>
EXECUTE
@RC
=
HelloWorld3
'Edward',
@Val2='
HeiHei
';
10>
PRINT
@RC;
11>
END
12>
go
Hello
Edward
Good
Moning,
Nice
to
Meet
you!
0
Hello
Edward
Good
Night,
Nice
to
Meet
you!
0
Hello
Edward
Good
Night,
Bye!
0
Hello
Edward
Good
Moning,
HeiHei
!
0

Answer 2

存储过程不支持的可以考虑使用用户定义函数来实现，如：
CREATE
FUNCTION
Order_Customer
(@FirstName
varchar(20),@LastName
varchar(20))
RETURNS
@Order_

Answer 3

例如定义一个变量
minid
是时间类型的，然后再查询这个变量的语句是
declare
@minid
datetime;
select
@minid
=
min(createtime)
from
tableA;