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SQL help for a newb

SQL help for a newb

SQL help for a newb

Ok, so I have a normalized DB. One table(links) has a source column and a destination column both of which are FK'ed to a locations table. I have product moving between fixed locations so I'd prefer one table with the locations.

I'm trying to querie the DB and list a full order that shows the correct source and destinations. Here's what I've tried thus far:


transport_tracker=# create table locations(
transport_tracker(# locationID serial primary key not null,
transport_tracker(# location varchar(25));


transport_tracker=# create table links(
transport_tracker(# linkID serial primary key not null,
transport_tracker(# source int references locations(locationID),
transport_tracker(# destination int references locations(locationID));


transport_tracker=# select locations.location as sources, locations.location as destinations
transport_tracker-# from links, locations, locations as loc2
transport_tracker-# where locations.locationid = links.source
transport_tracker-# and loc2.locationid = links.destination;

and this is what I get:


       sources       |     destinations
 texas               | texas
 washington          | washington
 guam                | guam
(3 rows)
What I 'should get' however is this:


       sources       |     destinations
 texas               | paris
 washington          | tokyo
 guam                | michigan
(3 rows)
I edited the above manually to show what I should get...

My basic question is how do I write a querie that pulls different pieces of information from one table foreign keyed two two columns of another table? Or, to put another way, how do I write a querie to pull my source and destination information from my locations table?

Thanks a lot.

RE: SQL help for a newb



transport_tracker=# select locations.location as sources, loc2.location as destinations

RE: SQL help for a newb

Worked great xwb. Thanks a lot.

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