multicolumn index vs two indexes

Hello:

I have a table whith an id field, a date field and 5 millions rows. I
need make queries like

select *on table where id='001' and fecha >='1-1-1999' and fecha
<'1-1-2000';

What is better? To create a multicolumn btree index with (date, id) or
two indexes, one btree for the date and a hash for the id? Where can I
find mor accurate info about indexes? (the manual is a little bit short
of it).

Thanks

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Salva