case-sensitivity inconsistency in quoted column aliases in FROM subselects

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                        POSTGRESQL BUG REPORT TEMPLATE
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Your name        :   Mike Hoolehan
Your email address    : mike@sycamorehq.com


System Configuration
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  Architecture (example: Intel Pentium)      :  Intel Pentium

  Operating System (example: Linux 2.0.26 ELF)     :  RH 7.2, Kernel 2.4.9-13

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

  Compiler used (example:  gcc 2.95.2)        : gcc 2.96 (rpm version)


Please enter a FULL description of your problem:
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if a quoted column alias in a FROM clause sub-select contains upper-case
chars, then that column cannot be later referenced without using quotes




Please describe a way to repeat the problem.   Please try to provide a
concise reproducible example, if at all possible:
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SELECT * FROM (SELECT col1 as "Foo" from table1) AS innerQuery
  WHERE Foo = 'whatever';
results in
"ERROR:  Attribute 'foo' not found"
no matter what capitalization is used for "Foo" in the where clause
(i.e. foo='whatever', FOO='whatever', etc).
I assume this is a bug, since if the column is aliases as "foo" (with
quotes, all lowercase), then the column can later be referenced
without quotes with case-insensitivity.



If you know how this problem might be fixed, list the solution below:
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