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master & slave table problem


_confused_

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help! how to i reference a record from master table when it doesn't have a child record? below is a sample i got from the postgreSQL manual & my problem is rather similar to that. how should i write my sql query so that CAT will also appear but the vegetable column for it is empty?

 

i've tried using MS Access and the records retrieved is correct. The sql query goes like this:

SELECT animal.animal_id, vegetable.*

FROM animal LEFT JOIN vegetable ON animal.animal_id = vegetable.animal_id;

 

test=> SELECT * FROM animal;
animal_id | name
-----------+-----------------
507 | rabbit
508 | cat
(2 rows)

test=> SELECT * FROM vegetable;
animal_id | name
-----------+-----------------
507 | lettuce
507 | carrot
507 | nut
(3 rows)

test=> SELECT *
test-> FROM animal, vegetable
test-> WHERE animal.animal_id = vegetable.animal_id;
animal_id | name | animal_id | name
-----------+-----------------+-----------+-----------------
507 | rabbit | 507 | lettuce
507 | rabbit | 507 | carrot
507 | rabbit | 507 | nut
(3 rows)

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