"Angus B. Atkins-Trimnell" <trimnell@uic.edu> writes:
> I am having trouble with a function designed to return all column
> constraints on a table.
I think the problem is that you're declaring the contype return column
as char (ie, character(1)) when pg_constraint.contype is actually "char"
(a historical PG datatype that's really just a single byte). The naming
confusion is unfortunate but we've never bitten the bullet to rename
"char" to something else.
Use quotes, or explicitly cast the catalog column to regular char
in the function's query.
regards, tom lane