varchar.diff
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This patch was necessary for the OpenLink Postgres Database Agent.
I think this fixes a bug anyway.
The following query demonstrates this bug:
create table foo (bar varchar);
insert into foo values (''); -- no problem
select * from foo where bar = ''; -- fails
causes segmentation fault.
Thanks to: Salvador Ortiz Garcia, Robert Patrick, Paul 'Shag' Walmsley,
and James Cooper for finding and fixing the problem.