General Bug Report: regexp beginning of line doesn't work properly

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POSTGRESQL BUG REPORT TEMPLATE
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Your name : Petr Hubeny
Your email address : psh(at)seznam(dot)cz

Category : runtime: back-end
Severity : serious

Summary: regexp beginning of line doesn't work properly

System Configuration
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Operating System : Linux 2.2.1 ELF

PostgreSQL version : 6.4.2

Compiler used : gcc 2.7.2.3

Hardware:
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PII-300MHz, 64M RAM
Linux agatha 2.2.1pcsp #6 t nor 2 16:17:30 CET 1999 i686 unknown

Versions of other tools:
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GNU Make version 3.76.1
flex version 2.5.4
GNU Bison version 1.25

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Problem Description:
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"select...where a ~ '^A'" doesn't return anything,
while "select...where a ~ '^[A]'" does. Also LIKE is
affected.

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Test Case:
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create table test (a text);
insert into test values ('ABC');
insert into test values ('DEF');
select * from test where a ~ '^A'; -- NOTHING!!!, Query 1
select * from test where a ~ '^[A]'; -- ABC, Query 2
select * from test where a LIKE 'A%'; -- NOTHING
select * from test where a LIKE '%A%'; -- ABC
select * from test where a LIKE '%F'; -- DEF

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Solution:
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Well, I suspect the parser and I tried to dig through
the code, and this is how far I was able to get:

with query 1 is function transformStmt()
erroneously called with

((A_Expr*)((SelectStmt*)parseTree)->whereClause)->oper == 263

with query 2 is

((A_Expr*)((SelectStmt*)parseTree)->whereClause)->oper == 465

Hope it helps,

Psh

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