#5023 Add impossible clause for no values listed

pkp · Sep 13, 2019 · e690d3e · e690d3e
1 parent 6ca1c06
commit e690d3e
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/classes/statistics/PKPMetricsDAO.inc.php b/classes/statistics/PKPMetricsDAO.inc.php
@@ -146,13 +146,16 @@ function &getMetrics($metricType, $columns = array(), $filters = array(), $order
 				if (is_scalar($values)) {
 					$currentClause .= "$column = ?";
 					$params[] = $values;
-				} else {
+				} elseif (count($values)) {
 					$placeholders = array_pad(array(), count($values), '?');
 					$placeholders = implode(', ', $placeholders);
 					$currentClause .= "$column IN ($placeholders)";
 					foreach ($values as $value) {
 						$params[] = $value;
 					}
+				} else {
+					// count($values) == 0: No matches should be returned.
+					$currentClause .= '1=0';
 				}
 			}