Solved

Follow-up question, Dynamic PIVOT query

Posted on 2014-09-11
6
201 Views
Last Modified: 2014-09-11
Previous question here.

In the previous question, I forgot to mention that my production table was not exactly as listed because I assumed I could make the modifications I needed to the final query to pass in an additional variable @Product (values of 'Gas', 'Oil', 'Water') and select the appropriate column using a Case statement.  So, the following query works.
SET DATEFORMAT mdy;

Declare @Product nvarchar(5)
Declare @StartDate datetime2
Declare @EndDate datetime2
SET @Product = 'Gas'
Set @StartDate = '2014-09-01'
SET @EndDate = '2014-09-30'

--Define the string of dates to use in the Pivot clause
DECLARE @docDatesTable TABLE
(
	[docDate] Datetime
);

INSERT INTO @docDatesTable
SELECT DISTINCT docDate FROM tbl_sysProduction
WHERE docDate >= @StartDate AND docDate < DATEADD(day, 1, @EndDate);

--Build the String containing the date values to be used in the pivot
DECLARE @docDates VARCHAR(MAX);
SELECT @docDates = COALESCE(@docDates + '],[', '') +
		  (LEFT(CONVERT(VARCHAR, [docDate], 101),6) + RIGHT(YEAR([docDate]),2))
FROM @docDatesTable ORDER BY [docDate]

--Build the dynamic SQL String
DECLARE @sql NVARCHAR(MAX);
SET @sql = 'SELECT * FROM (
SELECT IsNull(W.Bolo_ID, F.Bolo_ID) as Bolo_ID
, IsNull(W.Common_Name, F.Facility_Name) as Well_Facility
, P.[Entity_ID]
, P.[docDate]
, Volume = [Gas] 
FROM tbl_sysProduction as P
LEFT JOIN tbl_sysWells as W ON P.Entity_ID = W.Entity_ID
LEFT JOIN tbl_sysFacilities as F on P.Entity_ID = F.Entity_ID
) AS [SubTable]
PIVOT
(
     SUM([Volume])
FOR [docDate] IN ([' + @docDates + '])
) AS [Pivot]
ORDER BY Bolo_ID, Well_Facility;
';

EXEC sp_executesql @sql;

Open in new window

But when I replace this line:
, Volume = [Gas]

Open in new window

with:
, Volume = CASE WHEN ' + @Product + ' = ''Gas'' THEN [Gas]
                WHEN ' + @Product + '= ''Oil'' THEN [Oil]
                WHEN ' + @Product + '= ''Water'' THEN [Water]
                ELSE NULL END

Open in new window

I get an error message:
Msg 8114, Level 16, State 5, Line1
Error converting data type varchar to float

I also tried it with:
, Volume = CASE WHEN @Product = ''Gas'' THEN [Gas]
                WHEN @Product = ''Oil'' THEN [Oil]
                WHEN @Product = ''Water'' THEN [Water]
                ELSE NULL END

Open in new window

but that raised an error also:
Must declare variable "@Product"

So, the question is, how do I pass in a value for the Product (@Product) and retrieve the correct column from tbl_sysProduction based on that value in the dynamic SQL Statement?
0
Comment
Question by:Dale Fye (Access MVP)
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 2
6 Comments
 
LVL 2

Expert Comment

by:Sytech Solutions
ID: 40317982
Hi Dale

Do you mind posting the design of the table so I can see what the data types for the Gas, Oil and Water columns are?

Thanks
0
 
LVL 2

Accepted Solution

by:
Sytech Solutions earned 500 total points
ID: 40318023
Bit of a stab in the dark without the tables but try this:

SET @sql = 'SELECT * FROM (
SELECT IsNull(W.Bolo_ID, F.Bolo_ID) as Bolo_ID
, IsNull(W.Common_Name, F.Facility_Name) as Well_Facility
, P.[Entity_ID]
, P.[docDate]
, Volume = CASE ''' + @Product + ''' WHEN ''Gas'' THEN [Gas]
                WHEN  ''Oil'' THEN [Oil]
                WHEN ''Water'' THEN [Water]
                ELSE NULL END
FROM tbl_sysProduction as P
LEFT JOIN tbl_sysWells as W ON P.Entity_ID = W.Entity_ID
LEFT JOIN tbl_sysFacilities as F on P.Entity_ID = F.Entity_ID
) AS [SubTable]
PIVOT
(
     SUM([Volume])
FOR [docDate] IN ([' + @docDates + '])
) AS [Pivot]
ORDER BY Bolo_ID, Well_Facility;
';

Open in new window


Thanks
0
 
LVL 48

Author Comment

by:Dale Fye (Access MVP)
ID: 40318024
And your name is?

CREATE TABLE [dbo].[tbl_sysProduction](
	[Prod_ID] [int] IDENTITY(1,1) NOT NULL,
	[Entity_ID] [int] NOT NULL,
	[docDate] [datetime] NOT NULL,
	[Oil] [float] NULL,
	[Gas] [float] NULL,
	[Water] [float] NULL,
	[TimeStamp] [timestamp] NOT NULL,
 CONSTRAINT [PK_tbl_sysProduction] PRIMARY KEY CLUSTERED 
(
	[Prod_ID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

Open in new window

Although I've accessed data from SQL Server a lot in the past, I've only recently really started building my own, so selection of float may have been the wrong datatype to emulate a double in Access.
0
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 2

Expert Comment

by:Sytech Solutions
ID: 40318031
it's Ben. Float is correct for a double.

Thanks
0
 
LVL 48

Author Closing Comment

by:Dale Fye (Access MVP)
ID: 40318039
That took care of it.  I should have done a SELECT on the value of @SQL before trying to execute it and it would have been obvious.
0
 
LVL 2

Expert Comment

by:Sytech Solutions
ID: 40318041
Yay excellent.
0

Featured Post

The Ultimate Checklist to Optimize Your Website

Websites are getting bigger and complicated by the day. Video, images, custom fonts are all great for showcasing your product/service. But the price to pay in terms of reduced page load times and ultimately, decreased sales, can lead to some difficult decisions about what to cut.

Question has a verified solution.

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

International Data Corporation (IDC) prognosticates that before the current the year gets over disbursing on IT framework products to be sent in cloud environs will be $37.1B.
A Stored Procedure in Microsoft SQL Server is a powerful feature that it can be used to execute the Data Manipulation Language (DML) or Data Definition Language (DDL). Depending on business requirements, a single Stored Procedure can return differe…
This videos aims to give the viewer a basic demonstration of how a user can query current session information by using the SYS_CONTEXT function
Viewers will learn how to use the INSERT statement to insert data into their tables. It will also introduce the NULL statement, to show them what happens when no value is giving for any given column.

688 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