如何在SQL Sever Select语句中编写if条件以创建存储过程

Question

i am writing one stored procedure using sql server2008(dynamic sql), now my problem is i am passing 4 values to stored procedure in that UserAgentID varchar(50) pass the value or empty, now i can pass any value like(1233) based on that display the values and i am passing empty like('') now based on the field null values displayed but i am taking table Agentid is Integer datatype so i am passing IS NULL how to write the condition base on that , i am trying like this

ALTER Procedure [dbo].[usp_GetSearch123]      
(      
 @SearchValue varchar(100),      
 @SearchBy varchar(250),
 @DbName varchar(50),
 @UserAgentID varchar(50)     
)     
AS    
Begin

  Declare @cmd varchar(5000)

  select @cmd = 
  'Select QT.Name,SC.Name as Status,QT.QuoteNumber,QT.SubmissionNumber,QT.UnderWriter as UnderWriter,LC.Name as LineCode,QT.DBAName as DBAName         
  from Agent_Quote QT,Users US,' + @DbName + '..StatusCode SC, ' + @DbName+'..Linecode LC      
  where QT.StatusCode = SC.StatusCode And QT.LineCode = LC.LineCode and SC.StatusCode!=''C'' and US.UserID=QT.CreatedBy and US.AgentID like'''+@UserAgentID+''' and     
  (QT.Name like ''' + @SearchValue + '%'' or QT.DBAName like ''' + @SearchValue +'%'')       
  order by QT.Name,QuoteNumber desc'
print @cmd
  exec(@cmd)
 end

now i am passing empty in user table null values there so how to write the condition pls help me any one... thank u hemanth

Answer 1

You can try something like this

IF ISNULL(@UserAgentID, -1) = -1
  select @cmd = 
  'Select QT.Name,SC.Name as Status,QT.QuoteNumber,QT.SubmissionNumber,
  QT.UnderWriter as UnderWriter,LC.Name as LineCode,QT.DBAName as DBAName         
  from Agent_Quote QT,Users US,' + @DbName + '..StatusCode SC, ' + @DbName+'..Linecode LC      
  where QT.StatusCode = SC.StatusCode And QT.LineCode = LC.LineCode and 
  SC.StatusCode!=''C'' and US.UserID=QT.CreatedBy and 


  US.AgentID is nulll and     


  (QT.Name like ''' + @SearchValue + '%'' or QT.DBAName like ''' + @SearchValue +'%'')     


  order by QT.Name,QuoteNumber desc'
else
  select @cmd = 
  'Select QT.Name,SC.Name as Status,QT.QuoteNumber,QT.SubmissionNumber,
  QT.UnderWriter as UnderWriter,LC.Name as LineCode,QT.DBAName as DBAName         
  from Agent_Quote QT,Users US,' + @DbName + '..StatusCode SC, ' + @DbName+'..Linecode LC      
  where QT.StatusCode = SC.StatusCode And QT.LineCode = LC.LineCode and 
  SC.StatusCode!=''C'' and US.UserID=QT.CreatedBy and 


  US.AgentID like'''+@UserAgentID+''' and     


  (QT.Name like ''' + @SearchValue + '%'' or QT.DBAName like ''' + @SearchValue +'%'')       
  order by QT.Name,QuoteNumber desc'

or

  select @cmd = 
  'Select QT.Name,SC.Name as Status,QT.QuoteNumber,QT.SubmissionNumber,
  QT.UnderWriter as UnderWriter,LC.Name as LineCode,QT.DBAName as DBAName         
  from Agent_Quote QT,Users US,' + @DbName + '..StatusCode SC, ' + @DbName+'..Linecode LC      
  where QT.StatusCode = SC.StatusCode And QT.LineCode = LC.LineCode and 
  SC.StatusCode!=''C'' and US.UserID=QT.CreatedBy and 


  ((@UserAgentID is null AND US.AgentID is null) OR US.AgentID like'''+@UserAgentID+''') and     


  (QT.Name like ''' + @SearchValue + '%'' or QT.DBAName like ''' + @SearchValue +'%'')       
  order by QT.Name,QuoteNumber desc'

Answer 2

The question is a bit confusing but if it is centered on the AgentID issue, I'm going to make the following assumptions:

1) AgentID in your table has data type of int

2) You also have NULL values in the AgentID column

So with you passing in that variable as a string (which you should not do, keep data types consistant and pass in 0 or other non-valid id value) you could try doing your AgentID condition as follows:

--First, create int prameter and validate the @UserAgentID parameter
DECLARE @AgentID int
SELECT @AgentID = 0
IF ISNUMERIC(@UserAgentID)=1
BEGIN
SELECT @AgentID = CAST(@UserAgentID AS int)
END

--update your @UserAgentID condition statement as follows
    ... and ISNULL(US.AgentID,0) = '+CAST(@AgentID AS nvachar(10))+' and 

...

if your agentid is a varchar type column then the following should work...

... and ISNULL(US.AgentID,'') like ''' + ISULL(@UserAgentID,'') + ''' and

Again, the conditional statement and data types are throwing me here (need a "LIKE" for an ID column?) but hopefully this leads you in the right direction.

HTH

Dave