Solved

Any problems with nested expressions?

Posted on 2014-01-31
2
203 Views
Last Modified: 2014-02-05
Hello - is there a hard & fast rule about nested expressions in Access (2010) queries, like:
Sum(1) As CountOfTotalTickets, Sum(IIf([Hours] > 0,1,0)) As CountOfTicketsWithHours, [CountOfTicketsWithHours]/[CountOfTotalTickets] As PctTicketsWithHours

I know I could do this in a single expression, but this is just one simple example from a large set of qry's I have to work up where it gets more complicated than this.

Also, I'm trying to structure these qry's in a way that I can pull them up in datasheet view and demo that the math is being done correctly (a "show your  work" kind of thing)

On occasion, I have done this with no problems, and other times, it would get flaky on me.  

Thanks
0
Comment
Question by:mlagrange
2 Comments
 
LVL 4

Accepted Solution

by:
Jack Leach earned 250 total points
ID: 39824143
No issues other than readability.  Because of readability, sometimes things get a little flaky (especially with the query designer or SQL view, as the fonts are horrible for this type of stuff).

I tend to build SQL and expressions in Notepad++ using Poor Man's T-SQL formatter, then drop them into the SQL View of a query.  Having highlighting for opening/closing brackets and being able to see things monospaced and multi-line is a huge help for stuff like this.

As far as processing goes though, nope.  Just make sure your logic and arguments are correct.

Cheers,
-jack
0
 
LVL 15

Assisted Solution

by:JimFive
JimFive earned 250 total points
ID: 39824148
If there is any ambiguity due to the names used in the calculation then it won't work.  It is safer to always just redo the calculation (Sum(1)/Sum(iif(hours>0,1,0))), or do the final calculation in the report/form control.
0

Featured Post

Industry Leaders: 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!

Question has a verified solution.

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

As tax season makes its return, so does the increase in cyber crime and tax refund phishing that comes with it
This article describes two methods for creating a combo box that can be used to add new items to the row source -- one for simple lookup tables, and one for a more complex row source where the new item needs data for several fields.
What’s inside an Access Desktop Database. Will look at the basic interface, Navigation Pane (Database Container), Tables, Queries, Forms, Report, Macro’s, and VBA code.
In Microsoft Access, when working with VBA, learn some techniques for writing readable and easily maintained code.

713 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