Обсуждение: PostgresSQL 7.1.3 not parsing SELECT portion of SQL correctly

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                        POSTGRESQL BUG REPORT TEMPLATE
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Your name  : Mark Jeacocke
Your email address : mbj@ezytools.com


System Configuration
---------------------
  Architecture (example: Intel Pentium)   : AMD Athlon XP  1600

  Operating System (example: Linux 2.0.26 ELF)  : RedHat Linux 7.0 Kernel
2.4.2

  PostgreSQL version (example: PostgreSQL-7.1.3):   PostgreSQL-7.1.3

  Compiler used (example:  gcc 2.95.2)  : Downloaded offical RPMS from
Postgres mirror


Please enter a FULL description of your problem:
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Seems to be a parsing problem in the select portion of the SQL statement:

select DISTINCT TABLEID, '' AS ALIAS from TABLE; :FAILS
select DISTINCT TABLEID, 'test' AS ALIAS from TABLE; :FAILS
select DISTINCT TABLEID, Null AS ALIAS from TABLE; :FAILS
select DISTINCT TABLEID, trim('') AS ALIAS from TABLE; :SUCCEEDS
select DISTINCT TABLEID, 2 AS ALIAS from TABLE;         :SUCCEEDS

I believe all five queries should succeed.


Please describe a way to repeat the problem.   Please try to provide a
concise reproducible example, if at all possible:
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See above.



If you know how this problem might be fixed, list the solution below:
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"Mark Jeacocke" <mbj@ezytools.com> writes:
> select DISTINCT TABLEID, '' AS ALIAS from TABLE; :FAILS

We get this type of complaint regularly.  Perhaps DISTINCT should
resolve unknown-type inputs to "text", much as we do with CASE
and UNION constructs when we see an untyped literal.  Thoughts?

            regards, tom lane

PS: in the meantime, Mark, try casting the literal to text.

Is this a TODO item?  Seems so.  Comments?

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Tom Lane wrote:
> "Mark Jeacocke" <mbj@ezytools.com> writes:
> > select DISTINCT TABLEID, '' AS ALIAS from TABLE; :FAILS
>
> We get this type of complaint regularly.  Perhaps DISTINCT should
> resolve unknown-type inputs to "text", much as we do with CASE
> and UNION constructs when we see an untyped literal.  Thoughts?
>
>             regards, tom lane
>
> PS: in the meantime, Mark, try casting the literal to text.
>
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