I have some data I'm going to be parsing to store in a database. This data has a dozen to two dozen fields. The problem is that not every "record" has all of these fields, so one record might have 12 fields, and the next one only has 5 and the next has 24. So my problem is, how should I design a table to accomodate this?


Option 1: The first thought is to keep it simple, simply create a table with the thirty odd columns that can actually appear in the data and then leave the fields null if the data doesn't provide it.

Having 30+ columns in a RDBMS just seemed like a bad design to me though, so I'm unsure if this is a good idea. I can't really quote anything concrete either way, but this just "Feels" wrong.


Option 2: The second thought was to have two tables. The first table would have all of the data that every record posesses, and the second table would basically have 3 columns: belongs-to, type, value, so I could record all of the extra data there.

I'm sure I've seen people recomend against this strategy however, and it also feels kind of nasty.


Option 3: Again make a table that just has columns for the data that every record has, but add an extra column to store a seralized perl datastructure that contains the extra data for a particular record.

Again this seems like a bad idea because then the database can't natively access this extra data, with all the problems that entails.


So none of the solutions "feel" very good, which is why I come here. Is one of these solutions better than the others, good enough to use? Or is there a better way to solve this problem?

In reply to (OT) Database design: omitted partially filled fields. by BUU

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