Warning: pg_query(): Query failed: ERROR: duplicate key value violates unique constraint "objectcache_keyname_key" DETAIL: Key (keyname)=(wiki:valid-tags) already exists. in /usr/share/mediawiki/includes/db/DatabasePostgres.php on line 254

Warning: pg_query(): Query failed: ERROR: current transaction is aborted, commands ignored until end of transaction block in /usr/share/mediawiki/includes/db/DatabasePostgres.php on line 254
MediaWiki internal error.

Exception caught inside exception handler.

Set $wgShowExceptionDetails = true; at the bottom of LocalSettings.php to show detailed debugging information.