regcomp failed with error empty (sub)expression?

Hello all,

I just discovered the regex (regular expression matching in PGSQL 7.0.3...
However, after trying to run my first query I got the following:

regcomp failed with error empty (sub)expression

Anys thoughts as to what this means?

The following SQL statement generated the error.

INSERT INTO table3(table1.oid,table2.oid)
SELECT table1.oid, table2.oid
FROM table1, table2
WHERE table1.field1 ~* table2.field1
table1.field2 ~* table2.field2
table1.field3 = table2.field3
table1.field4 = table2.field4;

Field 1 - 4 on both table 1 and table 2 are all "text", and table1 field1 &
2 are in Upper/Lower vs table2 field1 & 2 are in all UPPER.

I'm basically trying to do a simply comparison between table1 and table2 to
find duplicates, but the case differences are stopping me, and as the 7.0.3
version of "upper()" has memory leaks, and the Plperl verion of uc() that I
created takes A LONG time to run (I have a LOT of records)... here I am
trying to match strings with CASE differences.

Any help would be appreciated, as to what caused this error.

Michael Miyabara-McCaskey
Email: mykarz(at)miyabara(dot)com
Web: http://www.miyabara.com/mykarz/
Mobile: +1 408 504 9014