SQL Server stored procedures Return, output parameters and tips

SQL Server is now becoming one of the most important operating system, database management system WindowNT above, with the introduction of SQL Server2000, Microsoft's such a database service system truly realized in WindowsNT / 2000 family of operating systems dominance in Microsoft's operating system, without any kind of database system can compete with them, including the database world leader in Oracle's Oracle database, including housekeeping. Admittedly, the biggest drawback is that SQL Server only runs on Microsoft's own operating system, and this is a fatal point of SQL Server. On the other hand it has become the best promoters to promote their own on top of SQL Server only "land" will play its functions to the extreme maximize the use of a variety of potential NT family of operating systems! As important SQL Server database system, a concept that is stored procedure, rational use of stored procedures, can effectively improve the performance of the program; and the business logic is encapsulated stored procedures in the database system can greatly improve the entire software system maintainability, when your business logic changes, eliminating the need to modify and compile the client application and redistribute them to the hands of a large number of users, you only need to modify the corresponding business logic on the server side implementation of a stored procedure that is can. Write your own reasonable needs of stored procedures, you can maximize the use of resources of SQL Server. Let us look at a variety of skill experience writing SQL Server stored procedures and use of stored procedures.

 

Input This parameter is only used to transfer information from the application to the stored procedure. 

InputOutput This parameter can transfer information from the application to the stored procedure and the process of transmitting information from the storage back to the application. 

Output This parameter is only used for the application of information transmitted back from a stored procedure. 

This parameter represents the return value ReturnValue stored procedure. SQL Server stored procedure parameter list is not displayed in this parameter. RETURN statement with a stored procedure only in the values ​​associated.

　　After the primary key stored procedure to generate a new value, typically using the RETURN statement in the stored procedure returns the value, used to access the parameter value type is ReturnValue parameters. 

 

1, with no simple procedure stored input parameters

if object_id('up_user') is not null

drop proc up_user

go

create proc up_user

as

set nocount on

delcare @name varchar(10)

begin

select @name=uname from user

end

set nocount off

go

esec up_user

 

2, the stored procedure with a simple input parameters

 if object_id('up_user') is not null

drop proc up_user

go

create proc up_user

@id int

as

set nocount on

delcare @name varchar(10)

begin

select @name=uname from user where  uid=@id

end

set nocount off

go

- execute the stored procedure

esec up_user 1

 

3, the stored procedure with parameters Return

 if object_id('up_user') is not null

drop proc up_user

go

create proc up_user

as

set nocount on

delcare @age int

begin

select @age=uage from user

return @age

end

set nocount off

go

 

- execute the stored procedure

declare @age int

exec @age=up_user

select @age

 

4, the output parameter is a stored procedure with

 if object_id('up_user') is not null

drop proc up_user

go

create proc up_user

@id int,

@name varchar(10) ='' output

as

set nocount on

begin

select @name=uname from user where uid=@id

end

set nocount off

go

 

- execute the stored procedure

declare @name varchar(10)

exec up_user 2, @name output

select @name

 

5, while the stored procedure with the output parameter and the Return

if exists(select name from sysobjects where name='up_user' and type='p')

drop proc up_user

go

create proc up_user

@id int,

@name varchar(20) output

as

declare @age int

begin

select @age=stuage,@name=stuname from stuinfo where uid=@id

return @age

end

 

- execute the stored procedure

declare @age int

declare @name varchar(20)

exec @age=up_user 2,@name output

select @age,@name

 

Attached: SQL Server system global variables

@@CONNECTIONS 

Returns the number of connections since the last start or trying to connect.

@@CURSOR_ROWS 

Returns the number of qualifying rows connected to the open end of the cursor currently exist (number of rows of data valid line is opened to return the cursor has not been read)

@@DATEFIRST 

Returns the first day of the week numbers

@@ERROR 

The last execution of SQL statements that return an error code.

@@FETCH_STATUS 

Returns the state last cursor FETCH statement executed, rather than the status of any currently open connections cursor.

@@IDENTITY 

Returns the last inserted identity value

@@ langId 

Returns the current language native language identifier (ID).

@@LANGUAGE 

Returns the name of the language currently in use.

@@LOCK_TIMEOUT 

Returns the current session of the current lock timeout setting in milliseconds.

@@PROCID 

Stored procedure to return the current process identifier (ID).

@@ROWCOUNT 

Returns the number of rows affected by the last statement.

@@SERVERNAME 

Returns the local name server is running.

@@SPID 

Returns the current server process identifier (ID) of the user process.

@@ TRANCOUNT 

Returns the number of currently active transactions connected.

@@VERSION 

Return date, version and type of processor currently installed.

@@CPU_BUSY

SQL Server returns since the last start of their working time in milliseconds CPU

@@DATEFIRST

Returns SET DATEFIRST command DATAFIRST parameter is assigned the value of SET DATEFIRST, command to specify the first day of the week is the week

@@DBTS

Returns the current timestamp value database must ensure the database timestamp value is only

@@ERROR

Returns an error code is executed Transact-SQL statement

@@FETCH_STATUS

FETCH statement returns the last state value

@@IDLE

SQL Server returns since launch last the length of time the CPU is empty closed state unit of milliseconds

@@IO_BUSY

SQL Server returns since the last start time of the CPU to perform input and output operations it takes in milliseconds

@@ langId

Returns the language ID value currently being used

@@LANGUAGE

Returns the name of the language currently in use

@@LOCK_TIMEOUT

Returns the current session length of time waiting for a lock in milliseconds,

@@MAX_CONNECTIONS

Returns the maximum number of connections allowed to connect to SQL Server

@@MAX_PRECISION

Back accuracy and decimal numeric data type

@@NESTLEVEL

Returns the current execution of the stored series of nested initial value of 0

@@OPTIONS

Return information about the current SET options

@@PACK_RECEIVED

SQL Server returns the input packet by reading the number of network

@@PACK_SENT

SQL Server returns the number of output packets addressed to the network

@@PACKET_ERRORS

Returns the number of errors of network packets

@@PROCID

Returns the ID value stored procedure

@@ REMSERVER

Returns the name of a remote SQL Server database server

@@SERVICENAME

SQL Server is running to return to the state under which services such as MSSQLServer MSDTC SQLServerAgent

@@SPID

The server returns the current user ID value processing process

@@TEXTSIZE

Statement of the SET SET TEXTSIZE option value defines the maximum length statement SELECT statement type of text or image data substantially bytes

@@ TIMETICKS

Returns the number of microseconds each clock

@@TOTAL_ERRORS

The number of disk read and write error is returned

@@TOTAL_READ

Returns the number of disk read operations

@@TOTAL_WRITE

Returns the number of disk write operations

@@ TRANCOUNT

Returns the number of transactions in the current connection in the active state

Reproduced in: https: //www.cnblogs.com/zhangchenliang/archive/2013/04/07/3006433.html