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Hello Victor,

I don't know how deep you are into relational database theory, but I suppose
you have defined all the necessary "foreign-keys" (= IDs) linking the tables
together. Having done so you have to use (eg.) a "left outer join" to "combine"
the correct info in the various tables. If you used only an "ordinary" join
you would not get tuples where there are no corresponding "IDs" in some tables.
I usually create some kind of "view" for such problems, e.g.

create view xyz as
select c1,c2,...,cx from
 ((tableA as
  left outer join tableB b on b.cxyz = a.czyx)
  left outer join tableC c on c....)
where ....
sort by ...
;
Then you would select (or maybe filter further) from the view.
Regards
H.S.

On Wed, 14 May 2014 15:54:03 +0200, Victor <victorbello@usal.es> wrote:

Hello.

I'm a new user of LO Base, and I have some problems that I haven't be able
to solve with tutorials.

I'm making a db with several tables with many records in each one, and I
want to retrieve records from several tables at the same time. Let me
explain my problem:

I have a "table A" with about 12000 records, with their IDs 1-12000. Then I
have other tables where some of those records have more data, and some
records are not present. I mean, in Table B, there are records 1-1000, in
table C 1001-2000, not necessary in that orther, but the point is that some
records are present in the tables are some aren't.

When I try to retrieve data from several tables, I'd want to have all the
records, no matter if they are present in all the tables or not.z

I hope I've explained myself clearly enough so you can help me.

Thank you very much.





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