Re: problem while converting sybase quries to postgres

Please cc: the list when you reply to me - that way others can help too.

imam wrote:
>>If this is a left outer join, you could do something like:
>>SELECT
>>  ...
>>FROM
>>  pe_pop_sr_posted_tran_head t1
>>LEFT JOIN
>>  pe_pop_po_header t2
>>ON
>>  t1.po_header_pk = t2.po_header_pk
>>LEFT JOIN
>>  pe_pop_sr_posted_tran_det t3
>>ON
>>  t2.po_header_pk = t3.po_header_pk
>>  AND t1.sr_tran_head_pk = t3.sr_tran_head_pk
>>
>>But you'll want to test it because I'm not clear what your query is doing.
>>--
>>   Richard Huxton
>>   Archonet Ltd
> 
> 
> Thanking for you reply the problem is that i have a "or" condition and left
> outer join between two table.A po_header_table is comman in both the join as
> given below
> t1.PO_HEADER_PK *= t2.PO_HEADER_PK or t3.PO_HEADER_PK *=
>>>t2.PO_HEADER_PK)

Ah! Hadn't spotted that. Would this be what you're after?

SELECT ... FROM
(
SELECT  t1.po_header_pk AS t1_phpk  t3.po_header_pk AS t3_phpk  ...
FROM  t1, t3
WHERE  t1.sr_tran_head_pk = t3.sr_tran_head_pk
)
AS first
LEFT JOIN
t2
ON (  first.t1_phpk = t2.po_header_pk  OR first.t3_phpk = t2.po_header_pk
)

Not sure what happens if t1_phpk and t3_phpk both match different rows 
in t2 or whether that's what you want.
--  Richard Huxton  Archonet Ltd