# Concatenated fields in a model **URL:** \ **Category:** Rails\ **Created:** [March 7, 2008, 8:17pm UTC](https://www.ruby-forum.com/t/concatenated-fields-in-a-model/131298 "2008-03-07T20:17:17Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![oldbug](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/c0e974/32.png) [@oldbug](https://www.ruby-forum.com/u/oldbug)\ **Post date:** [March 7, 2008, 8:17pm UTC](https://www.ruby-forum.com/t/concatenated-fields-in-a-model/131298/1 "2008-03-07T20:17:17Z")
Hello RoR community from a newbie! I have a document number “database” in which each document number consists of 3 parts: a 2 digit “document category” prefix, a 5 digit document number, and a 3 digit “document variation” suffix. (I quoted the word “database” because it is currently stored in a single spreadsheet). I can export that database to a CSV file and run a simple rake rule to load the CSV data into a model. (As a sidebar, if anybody wanted to point me in the direction of how to extract the data directly from the Excel spreadsheet instead of going through the CSV pipe first, I would be grateful.) Traditionally, our documents have been identified as “01-00032-000” or “20-01017-013”, and the data for the document number is stored in 3 columns in the spreadsheet. I can create my model with three separate columns based on the 3 columns from the spreadsheet, or I can concatenate them together as shown above. Ultimately, I would like to be able to display the list of documents grouped by document category (the 2 digit prefix), and perhaps even limit the display to those documents that fall into a certain category (00, 01, 02-09, 10-19, etc…). (As another aside, would I be better off creating a table identifying names of the 10-12 different categories by min/max category prefix, or better off coding those names in my specialized app?) I started off prototyping a model with the 3 columns separated and then naively combined them in my view with: \<%=h sprintf("%02d-%05d-%03d", document.document\_category\_prefix, document.primary\_document\_number, document.document\_variation) %\> It was quick. It was simple. It tought me that I can embed calls to ‘sprintf()’ in my view. I went to bed happy. Today I started investigating active scaffolding so I could get a much prettier view of the documents than the bare view shown by the default scaffolding. (I reasoned that, if the interface looks ugly, folks will think that the implementation is kludgy and buggy, but if it looks beautiful, they’ll think I’m a genios.) (That’s a joke, son.) I quickly ran into the issue of trying to figure out how I would combine the 3 columns of data in a nice sprintf() output with Active Scaffolding. The answer to that problem may be trivial, or it may not, but it quickly led me to my real question: Should I be combining data like this in a view in the first place? Or should that go somewhere in the model or controller? If so, how would I do that? (Asked in the tone of somebody who wrote his first RoR application last night.) I would appreciate any wisdom folks would care to share in this matter. –wpd ---
**Author:** ![oldbug](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/c0e974/32.png) [@oldbug](https://www.ruby-forum.com/u/oldbug)\ **Post date:** [March 7, 2008, 9:09pm UTC](https://www.ruby-forum.com/t/concatenated-fields-in-a-model/131298/2 "2008-03-07T21:09:51Z")
On 7 Mar 2008, at 19:16, Patrick D. wrote: > Should I be combining data like this in a view in the first place? Or > should that go somewhere in the model or controller? If so, how would > I do that? (Asked in the tone of somebody who wrote his first RoR > application last night.) Have you looked at composed\_of ? Fred ---
**Author:** ![oldbug](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/c0e974/32.png) [@oldbug](https://www.ruby-forum.com/u/oldbug)\ **Post date:** [March 7, 2008, 9:41pm UTC](https://www.ruby-forum.com/t/concatenated-fields-in-a-model/131298/3 "2008-03-07T21:41:38Z")
On Mar 7, 2:16 pm, “Patrick D.” [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > (As a sidebar, if > anybody wanted to point me in the direction of how to extract the data > directly from the Excel spreadsheet instead of going through the CSV > pipe first, I would be grateful.) Have you looked at parseexcel? [http://www.rubyrescue.com/?p=6](http://www.rubyrescue.com/?p=6) Other options: If you’re on the Windows Platform, there’s win32ole which can automate excel. If you’re on JRuby, you can interface with POI for excel parsing and creation. - Mark.