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PDOException: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '' at line 2: SELECT COUNT(r.id) as registered, r.periodicity FROM ibn_journal_numbers n LEFT JOIN ibn_journals r ON r.id=n.journal_id WHERE n.journal_id = 48 AND YEAR(n.published_on) = ; Array ( ) in getNumJournals() (line 5810 of /var/www/sites/idsi/ibn2014/trunk/sites/all/modules/Graph_Stacked/Graph_Stacked.module).
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