Subquery and where clause ?
| От | Bo Lorentsen | 
|---|---|
| Тема | Subquery and where clause ? | 
| Дата | |
| Msg-id | 3B83A32D.E75698B5@netgroup.dk обсуждение исходный текст | 
| Список | pgsql-novice | 
Hi ...
I have been trying to find a way to make several differant table
counters on one request, and therefor tried to use sub queries as my
solution, but I can't make it work and hope someone could help me out
:-(
Lets say I have 3 tables A, B and C and both A and B have a references
to C. I like to make a view that for each C counts the number of
refering A's and B's.
Tables :
CREATE TABLE A (
    INTEGER id,
    INTEGER ref );
CREATE TABLE B (
    INTEGER id,
    INTEGER ref );
CREATE TABLE C (
    INTEGER id );
As I can see it, the SQL would look somthing like this :
    SELECT C.id, A.count, B.count FROM C,
        (SELECT COUNT( A.id ) FROM A WHERE A.ref = C.id) AS A,
        (SELECT COUNT( B.id ) FROM B WHERE B.ref = C.id) AS B;
But the result is the same count for each row :-(
This is off cause a very simple example.
What have I done wrong ?
/BL
		
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