diff --git a/lib/cartodb/server_options.js b/lib/cartodb/server_options.js
index a98e09ae..3d0f016b 100644
--- a/lib/cartodb/server_options.js
+++ b/lib/cartodb/server_options.js
@@ -158,8 +158,9 @@ module.exports = function(){
     // last update in any of the given tables
     //
     me.findLastUpdated = function (username, api_key, tableNames, callback) {
-      var sql = 'SELECT EXTRACT(EPOCH FROM max(updated_at)) as max FROM CDB_TableMetadata m WHERE m.tabname::name = any (\'{'
-        + tableNames.join(',') + '}\')';
+      var sql = 'SELECT EXTRACT(EPOCH FROM max(updated_at)) as max FROM CDB_TableMetadata m WHERE m.tabname = any (ARRAY['+
+         tableNames.map(function(t) { return "'" + t + "'::regclass"; }).join(',') +
+      '])';
 
       // call sql api
       me.sqlQuery(username, api_key, sql, function(err, rows){