Changes

CREATE OR REPLACE FUNCTION cleanpatno (text) RETURNS bigint AS $$ if ($_[0]) { my $var=$_[0]; if ($var=~/^\d*$/) {return $var;} return undef; } return undef; $$ LANGUAGE plperl;

INSERT statement

INSERT INTO citation ( SELECT new_citations.citingpatentnumber, new_citations.citedpatent number FROM patents );

Equivalent COPY statement:

\COPY citations (SELECT new_citations.citingpatentnumber, new_citations.citedpatent number FROM patents) TO '/tmp/citations_merge_export.txt' DELIMITER AS E'\t' HEADER NULL AS CSV;

--COPY 1646225

Then copy CSV file into table:

\COPY citations_merged FROM '/tmp/citations_merge_export.txt' DELIMITER AS E'\t' HEADER NULL AS CSV; --1607724