Message-ID: <4B221CFF.4060200@gmx.net>
Date: Fri, 11 Dec 2009 11:20:47 +0100
From: Andreas <maps.on@gmx.net>
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To: PostgresSQL list <pgsql-sql@postgresql.org>
Subject: Re: Re: constants in 2-column foreign keys or how to design
	a storage for text-groups ?
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Jasen Betts schrieb:
> On 2009-12-09, Andreas <maps.on@gmx.net> wrote:
> ...
>   
>> stupid example:
>> ---------------
>> color:   red, green, blue
>> size: tiny, little, big, giant
>> structure:  hard, soft, floppy
>> How would I solve the rather common text storage issue?
>>     
>
> have you considered using enumerated types instead?
Yes, but I need those texts in the GUI to show them as listboxes or 
comboboxes.
There might be changes too when I later need to add or drop an option of 
a group.

E.g. there are questionnaires to model.
Lets say 10 questions where each has a couple of predefined answers 
where one should be selected.
So I've got to store every group of possible answers to a question 
either in a seperate table or in a kind of repository all within one big 
table (row_id, questionnare_id, question_id, answer_nr, answer)
The row_id so I just need to store 1 value per answer.

Now I've got to make sure that it is impossible that accidentally there 
gets a question-17 answer connected to a question-42 and above all, that 
the questions dont get mixed between the questionnaires.

I can do this with the frontend and enough hope that nothing bad will 
happen.
Still I'd rather hardwire the integrity into the table design.