Solved

using variables in whereclause

Posted on 2012-03-29
7
251 Views
Last Modified: 2012-03-29
Hi,
  I have something like below in my stored procedure

IF @physicianID = 0 OR @physicianID IS NULL
BEGIN
SET @whereClause = 'requestedby=@physicianID
            and examdate>=@startDate
            and examdate<=@endDate'
END
ELSE
BEGIN
SET @whereClause ='examdate>=@startDate
            and examdate<=@endDate'
END

and I used the variable @whereCluase like below

select
            examdate,
            patient_no
      from exams
      where @whereClause
      group by examdate,patient_no
Can I do like this? or please let me know how can I do that .

Thank you
0
Comment
Question by:Sthokala
  • 3
  • 3
7 Comments
 
LVL 51

Expert Comment

by:HainKurt
ID: 37783272
after your code do his

declare @sql varchar(max) = 'select ... from ...' + @whereClause
exec @sql
0
 
LVL 51

Expert Comment

by:HainKurt
ID: 37783288
oops, you need to work on this part too

SET @whereClause = 'requestedby=@physicianID
            and examdate>=@startDate
            and examdate<=@endDate'
>>>>
SET @whereClause = 'requestedby=' + @physicianID +
          ' and examdate>= ''' + @startDate + ''''
          ' and examdate<= ''' + @endDate + ''''
0
 
LVL 51

Expert Comment

by:HainKurt
ID: 37783311
and I guess there is logical error in your code "if... then ... else..." logic should be reversed...

so, final structure should be something like this

declare @whereClause varchar(max)
declare @startDate varchar(12)
declare @endDate varchar(12)
declare @physicianID int

IF isNull(@physicianID,0) = 0
BEGIN 
  SET @whereClause ='examdate >= ''' + @startDate + ''' and examdate <= ''' + @endDate + ''''
END
ELSE
BEGIN
  SET @whereClause = 'requestedby=' + @physicianID + ' and examdate>= ''' + @startDate + ''' and examdate<= ''' + @endDate + ''''
END

declare @sql varchar(max) = 'select ... from ...' + @whereClause
exec @sql

Open in new window

0
[Webinar] Disaster Recovery and Cloud Management

Learn from Unigma and CloudBerry industry veterans which providers are best for certain use cases and how to lower cloud costs, how to grow your Managed Services practice in IaaS clouds, and how to utilize public cloud for Disaster Recovery

 
LVL 69

Expert Comment

by:ScottPletcher
ID: 37783340
You have two choices:
    1.  Use one query, which tests the variable and column as needed.  
         This may not produce an optimal query plan every time it run.
    2.  Use dynamic SQL, which will produce an optimal query plan, but is more work
         to set up **and requires specific authorities being granted *directly* to the id
         used to run the SQL code**.


--1.
SELECT
            examdate,
            patient_no
      FROM dbo.exams
      WHERE
          (@physicianID = 0 OR @physicianID IS NULL OR requestedby = @physicianID) AND
          examdate>=@startDate and
          examdate<=@endDate'
      GROUP BY
          examdate, patient_no
0
 
LVL 69

Accepted Solution

by:
ScottPletcher earned 500 total points
ID: 37783367
--2.

DECLARE @sql nvarchar(max)

SET @sql = '
SELECT
            examdate,
            patient_no
      FROM dbo.exams
      WHERE
          examdate>=@startDate AND
          examdate<=@endDate
'

IF @physicianID > 0
    SET @sql = @sql + ' AND
           requestedby = ' + CAST(physicianID AS varchar(10))

SET @sql = @sql + '
       GROUP BY
          examdate, patient_no'

EXEC sp_executesql @sql, N'@startDate datetime, @endDate datetime', @startDate, @endDate
0
 

Author Comment

by:Sthokala
ID: 37783530
Hi,
  Thank you for your comments.  I tried below way

DECLARE @sql nvarchar(max)

SET @sql = ' INSERT INTO #TmpMUStatus
   SELECT count(*), (SELECT name from users where user_no='+CAST(@physicianID AS varchar(10))+') as physicianName,null,null,null,null,null,null,null,null,null,null,NULL,NULL from(
      SELECT
            examdate,
            patient_no
      FROM exams WHERE
          examdate>='+LEFT(CONVERT(VARCHAR, @startDate, 120), 10)
+' AND
          examdate<='+LEFT(CONVERT(VARCHAR, @endDate, 120), 10)

IF @physicianID > 0
    SET @sql = @sql + ' AND
           requestedby = ' + CAST(@physicianID AS varchar(10))

SET @sql = @sql + '
        GROUP BY examdate,patient_no) AS SourceQuery'
EXEC @sql


I am getting below error

Msg 203, Level 16, State 2, Procedure GenerateMUStats, Line 54
The name ' INSERT INTO #TmpMUStatus
   SELECT count(*), (SELECT name from users where user_no=73408) as physicianName,null,null,null,null,null,null,null,null,null,null,NULL,NULL from(
      SELECT
            examdate,
            patient_no
      FROM exams WHERE
          examdate>=2012-01-01 AND
          examdate<=2012-05-05 AND
           requestedby = 73408
        GROUP BY examdate,patient_no) AS SourceQuery' is not a valid identifier.
0
 
LVL 69

Expert Comment

by:ScottPletcher
ID: 37783579
EXEC (@sql) -- the parens are required


Since you want pass to the date values in, you also need additional quotes:

...
FROM exams WHERE
          examdate>='''+LEFT(CONVERT(VARCHAR, @startDate, 112), 8)
+''' AND
          examdate<='''+LEFT(CONVERT(VARCHAR, @endDate, 112), 8) + ''''
...
0

Featured Post

Ransomware-A Revenue Bonanza for Service Providers

Ransomware – malware that gets on your customers’ computers, encrypts their data, and extorts a hefty ransom for the decryption keys – is a surging new threat.  The purpose of this eBook is to educate the reader about ransomware attacks.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Data architecture is an important aspect in Software as a Service (SaaS) delivery model. This article is a study on the database of a single-tenant application that could be extended to support multiple tenants. The application is web-based develope…
How to leverage one TLS certificate to encrypt Microsoft SQL traffic and Remote Desktop Services, versus creating multiple tickets for the same server.
This Micro Tutorial will give you a basic overview how to record your screen with Microsoft Expression Encoder. This program is still free and open for the public to download. This will be demonstrated using Microsoft Expression Encoder 4.
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, just open a new email message. In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…

895 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

17 Experts available now in Live!

Get 1:1 Help Now