join multivalue variables with ,

public/app/plugins/datasource/postgres/postgres_query.ts

@@ -151,7 +151,7 @@ export default class PostgresQuery {
     }
 
     var escapedValues = _.map(value, kbn.regexEscape);
-    return '(' + escapedValues.join('|') + ')';
+    return '(' + escapedValues.join(',') + ')';
   }
 
   render(interpolate?) {