?
Solved

SQL using a string table field as a formula to calculate results in decimal form

Posted on 2011-02-11
3
Medium Priority
?
517 Views
Last Modified: 2012-05-11
I have a table which contains a data field which is in VARCHAR format that contains a formula. I would like to convert that formula into a decimal value in a new data field.

This is what one of the fields looks like:

CommonPrograms.dbo.cp_GreaterUDF(.05,(CommonPrograms.dbo.cp_GreaterUDF(.0225,225*.01) + 125*.01)) + 4.5

"CommonPrograms.dbo.cp_GreaterUDF" is a user-defined function that calculates the greater of two numbers. But there could be anything in that field. For example: the data field could contain: 2+3+6*100

Could you please send me code that will convert the VARCHAR field into a decimal data field which will now reflect the results of the formula?

Thanks!

0
Comment
Question by:LennyGray
3 Comments
 
LVL 143

Accepted Solution

by:
Guy Hengel [angelIII / a3] earned 2000 total points
ID: 34873189
you would need to run that expression somehow dynamically, which means you can only do it one row by one.
with sp_executesql you could then fetch the results...

declare @sql nvarchar(max)
declare @result decimal(20,5)

set @sql = ' set @res = ' + 'CommonPrograms.dbo.cp_GreaterUDF(.05,(CommonPrograms.dbo.cp_GreaterUDF(.0225,225*.01) + 125*.01)) + 4.5 '
exec sp_executesql @sql, N'@res decimal(20,5) output', @result OUTPUT
select @result 

Open in new window




0
 
LVL 9

Expert Comment

by:s_chilkury
ID: 34873227
Try casting :

CAST (DataField AS DECIMAL (3, 2))
0
 
LVL 61

Expert Comment

by:HainKurt
ID: 34873258
something like this may work
declare @CustId int32
  declare @Formula nvarchar(1000)
  declare @sql nvarchar(4000)
  
	declare CustList cursor for
	select custid, formula from myTable where ...

	OPEN CustList
	FETCH NEXT FROM CustList INTO @CustId, @Formula

	WHILE @@FETCH_STATUS = 0
	BEGIN
	  set @sql='update myTable set colX=' + @formula +' where CustID=' + @CustID;
	  exec @sql;
	  FETCH NEXT FROM CustList INTO @CustId, @Formula
	END

	CLOSE CustList
	DEALLOCATE CustList

Open in new window

0

Featured Post

What Kind of Coding Program is Right for You?

There are many ways to learn to code these days. From coding bootcamps like Flatiron School to online courses to totally free beginner resources. The best way to learn to code depends on many factors, but the most important one is you. See what course is best for you.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Windocks is an independent port of Docker's open source to Windows.   This article introduces the use of SQL Server in containers, with integrated support of SQL Server database cloning.
MSSQL DB-maintenance also needs implementation of multiple activities. However, unprecedented errors can hamper the database management. In that case, deploying Stellar SQL Database Toolkit ensures fast and accurate database and backup repair as wel…
Via a live example, show how to extract insert data into a SQL Server database table using the Import/Export option and Bulk Insert.
Via a live example, show how to backup a database, simulate a failure backup the tail of the database transaction log and perform the restore.

589 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