Обсуждение: Port Bug Report: Joins (does not support outer, left, right)

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                        POSTGRESQL BUG REPORT TEMPLATE
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Your name               : Deva Vejay
Your email address      : devavejay@preveho.com

Category                : runtime: back-end: SQL
Severity                : non-critical

Summary: Joins (does not support outer, left, right)

System Configuration
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  Operating System   : Linux 2.0.34

  PostgreSQL version : 6.2

  Compiler used      :

Hardware:
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Redhat, Pentium II 400 128 m Ram,


Versions of other tools:
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Problem Description:
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We are trying to migrate our product to Linux! and our
backend to Postgresql!! The major problem we are in countering
is that our product uses tons of outer, and left joins.
We were wondering if there is any method of limiting the result
set of a quary to mimic an outer or left join with out using
the keywords outer and left.

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Test Case:
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Solution:
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> Summary: Joins (does not support outer, left, right)
> We were wondering if there is any method of limiting the result
> set of a quary to mimic an outer or left join with out using
> the keywords outer and left.

For a left outer join:

select <cols> from t1, t2
 where t1.x = t2.x
union
select <t1 cols>, null,... from t1
 where t1.x not in (select t2.x from t2);


--
Thomas Lockhart                lockhart@alumni.caltech.edu
South Pasadena, California