|Subject||Re: [firebird-support] Newbie: A few questions...|
> > > 2. Does FireBird support Multi-component keys with mixed sort orders?1.5.
> > > For example 1 key, 2 fields, 1 ascending, and 1 descending?
> >No, sort orders are on a per-index basis. Primary, unique and Foreign
> >key auto-created indices are ASC only.
> You can create DESC primary (and matched order foreign) keys in Firebird
Oh yes, I forgot about that one. Quick question (and without trying):
what happens if you mix an ASC FK index with a DESC PK index?
> Data in Firebird are not stored in tabular structures at all and don'tneed
> to be. Mixed *sort* orders don't come from indexes in SQL, they arecreated
> by your SQL statement specification, in an ORDER BY clause. Speed can beObviously, I meant the sort-orders in the indices - not the sort orders
> gained for these sorts (sometimes) by defining indexes to support them,
> e.g. for
in a final resultset.
> order by col1 desc, col3ok ok ... 256 or its whereabouts... :-)
> you might gain some speed by creating a DESC index for col1 and an ASC
> index for col3.
> > > 3. What is the maximum key size in FireBird, and is it affected by
> > > the Database Page Size?
> 253 for character set NONE, 252 or less for all other character sets.
> There's a calculator here:
> Somebody in Norway, PLEASE send Martijn some Bamsemums,
> URGENTLY!! Clinical dosage necessary.
Darn... it's too hot today... and Yesterday, for that matter.
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