diff --git a/lib/cartodb/carto_data.js b/lib/cartodb/carto_data.js
index 1ec2c518..deafba8c 100644
--- a/lib/cartodb/carto_data.js
+++ b/lib/cartodb/carto_data.js
@@ -19,7 +19,6 @@ module.exports = function() {
         user_metadata_db: 5,
         table_metadata_db: 0,
         user_key:  "rails:users:<%= username %>",
-        map_key:   "rails:users:<%= username %>:map_key",
         table_key: "rails:<%= database_name %>:<%= table_name %>"
     };
 
@@ -63,8 +62,12 @@ module.exports = function() {
     me.checkMapKey = function(req, callback) {
         // strip subdomain from header host
         var username = req.headers.host.split('.')[0];
-        var redisKey = _.template(this.map_key, {username: username});
-        this.inSet(this.user_metadata_db, redisKey, req.query.map_key, callback);
+        var redisKey = "rails:users:" + username; 
+        this.retrieve(this.user_metadata_db, redisKey, "map_key", function(err, val) {
+            var valid = 0;
+            if ( val && val == req.query.map_key ) valid = 1;
+            callback(err, valid);
+        });
     };
 
     /**
diff --git a/test/prepare_db.sh b/test/prepare_db.sh
index 3e3a0419..b7ab4d9e 100755
--- a/test/prepare_db.sh
+++ b/test/prepare_db.sh
@@ -28,7 +28,8 @@ psql "${TEST_DB}" < ./sql/gadm4.sql
 echo "preparing redis..."
 echo "HSET rails:users:vizzuality id 1" | redis-cli -p ${REDIS_PORT} -n 5
 echo 'HSET rails:users:vizzuality database_name "'"${TEST_DB}"'"' | redis-cli -p ${REDIS_PORT} -n 5
-echo "SADD rails:users:vizzuality:map_key 1234" | redis-cli -p ${REDIS_PORT} -n 5
+echo "HSET rails:users:vizzuality map_key 1234" | redis-cli -p ${REDIS_PORT} -n 5
+echo "SADD rails:users:vizzuality:map_key 1235" | redis-cli -p ${REDIS_PORT} -n 5
 echo 'HSET rails:'"${TEST_DB}"':my_table infowindow "this, that, the other"' | redis-cli -p ${REDIS_PORT} -n 0
 
 echo "Finished preparing data. Run tests with expresso."