# How to structure a database table with arbitrary labels for the columns?

**URL:** <https://www.ruby-forum.com/t/how-to-structure-a-database-table-with-arbitrary-labels-for-the-columns/172983>\
**Category:** Rails\
**Created:** [July 30, 2009, 7:25pm UTC](https://www.ruby-forum.com/t/how-to-structure-a-database-table-with-arbitrary-labels-for-the-columns/172983 "2009-07-30T19:25:43Z")\
**Posts on this page:** 4\
**Page:** 1

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**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:** [July 30, 2009, 7:25pm UTC](https://www.ruby-forum.com/t/how-to-structure-a-database-table-with-arbitrary-labels-for-the-columns/172983/1 "2009-07-30T19:25:43Z")

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I am starting to think about writing an RoR app to store some 2-D  
data. Most of the data are textual, although there could be a column  
of dates or a column of numbers here and there. The issue is:  
different data sets have different columns.

Currently, the data are stored in spreadsheets. Many of the sheets  
share a common set of columns, but there are some differences (and  
more differences could be added later – after all, they are just  
spreadsheets, and I can change the heading at the top of a column and  
start filling in data for that column at will.)

Is this a common problem? If so, how have folks solved it?

One solution might be to say, “You are an agile RoR developer (ok,  
it’s a bit of a stretch, but for the purpose of this argument, let’s  
pretend it’s true), adding a column to a database is just as easy as  
adding a column to a spreadsheet. Design the application with the  
columns you know about today. Add more columns tomorrow when you  
discover/decide you need them.”

Another solution might be to create a table of headings for each  
column and create a table with just text values associated with each  
type of heading (and associated with the other table(s) to which the  
data belongs). Do the same thing for the numeric data and the date  
data. Design the application so it’s easy to add columns via the UI.

Another solution might be to do something completely different. Any  
ideas/suggestions?

–wpd

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<div class="post-metadata">

**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:** [July 30, 2009, 9:08pm UTC](https://www.ruby-forum.com/t/how-to-structure-a-database-table-with-arbitrary-labels-for-the-columns/172983/2 "2009-07-30T21:08:12Z")

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Hi Patrick,

On Thu, 2009-07-30 at 13:24 -0400, Patrick D. wrote:

> I am starting to think about writing an RoR app to store some 2-D  
> data.

> From your explanation / question below, I have to ask and do not mean to  
> put you off but, are you an experienced software developer? If not, I’d  
> strongly recommend you start slow. While I haven’t read it personally,  
> I’ve heard lots of recommendations for Chris P.'s “Learn to Program”  
> which teaches basic programming concepts using Ruby. As a second  
> course, you might try “Why’s (poignant) Guide to Ruby”.

After that, yes, the problem you discuss is very common. When you’re  
ready, go with your first proposed solution.

Best regards,  
Bill

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<div class="post-metadata">

**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:** [July 30, 2009, 9:48pm UTC](https://www.ruby-forum.com/t/how-to-structure-a-database-table-with-arbitrary-labels-for-the-columns/172983/3 "2009-07-30T21:48:35Z")

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Adding columns via code isn’t hard. You’ll have to double check that  
the new columns are picked up in your objects without having to  
restart the server when operating in production mode.

But the real question is, is there enough commonality between data  
sets that whatever you are trying to do is well solved using a  
database? The flexibility to just have data and not have it  
constrained by a schema is what spreadsheets are good at.

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<div class="post-metadata">

**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:** [July 31, 2009, 2:40am UTC](https://www.ruby-forum.com/t/how-to-structure-a-database-table-with-arbitrary-labels-for-the-columns/172983/4 "2009-07-31T02:40:04Z")

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On Thu, Jul 30, 2009 at 3:47 PM, cnk[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> database? The flexibility to just have data and not have it  
> constrained by a schema is what spreadsheets are good at.  
> Ohhh… Great answer!

I suspect I’ll just gather the data into the table that I know exists  
now. I was asking because (as is typical of me), I was dreaming about  
how I might bite off more than I could chew – wanting to allow the  
end user to create arbitrary data sets displayed in tabular form, with  
arbitrary names and types for the different columns.

But, as I’ve thought about it more, it has occurred to me that I will  
probably get 99.9% of the way where I want to be just by defining the  
table I need, and creating the relationships necessary to extract and  
edit specific data sets within that table.

But thanks for the great answer.

–wpd