How big is a billion triples?

Is it possible to relate the size of a triple store to a rough eq开发者_如何学Pythonuivalence in terms of a RDBMS? Or would this vary too much based on the type of data stored (in my case text content of a CMS)

I'm trying to get my head round how a 800MB database compares to a 1.7Billion triple triple store. I'm fully prepared to be told this is a daft question.

It's a difficult to answer question but it's not silly.

broadly speaking you can convert from from tables size to triple count with something like:

triples = columns - 1 * rows

It's a bit of an overgeneralisation, but it should give you some idea, e.g. if you have a table like:

prikey val1   val2
a      1      2
b      3      4
c      5      6

That would be 6 triples, if you're familiar with NTriples syntax, the triples would be:

<a> <val1> 1 .
<a> <val2> 2 .
<b> <val1> 3 .
<b> <val2> 4 .
<c> <val1> 5 .
<c> <val2> 6 .

In more complex sitatuions (like compound pirmary keys) it might be more or less than that, but it should give you some idea.