Fix update-schema constraint check on Postgres 12

pg_constraint.consrc has been removed in Postgres 12, and this is the recommended replacement.
See https://www.postgresql.org/docs/12/release-12.html

1 files changed, 1 insertions, 1 deletions

diff --git a/bin/update-schema b/bin/update-schema
index 8f31085c9..44e299b91 100755
--- a/bin/update-schema
+++ b/bin/update-schema
@@ -319,7 +319,7 @@ sub constraint_exists {
 # Returns true if a check constraint contains a certain string
 sub constraint_contains {
     my ( $constraint, $check ) = @_;
-    my ($consrc) = $db->dbh->selectrow_array('select consrc from pg_constraint where conname = ?', {}, $constraint);
+    my ($consrc) = $db->dbh->selectrow_array('select pg_get_expr(conbin, conrelid) from pg_constraint where conname = ?', {}, $constraint);
     return unless $consrc;
     return $consrc =~ /$check/;
 }