diff --git a/scripts-available/CDB_FederatedServer.sql b/scripts-available/CDB_FederatedServer.sql
index 324359f..43401f7 100644
--- a/scripts-available/CDB_FederatedServer.sql
+++ b/scripts-available/CDB_FederatedServer.sql
@@ -126,16 +126,21 @@ CREATE OR REPLACE FUNCTION @extschema@.__CDB_FS_credentials_to_user_mapping(inpu
 RETURNS jsonb
 AS $$
 DECLARE
-    user_mapping jsonb := json_build_object(
-        'user_mapping',
-        jsonb_build_object( 'user', input_config->'credentials'->'username',
-                            'password', input_config->'credentials'->'password')
-        );
+    mapping jsonb := '{}'::jsonb;
 BEGIN
     IF NOT (input_config ? 'credentials') THEN
         RAISE EXCEPTION 'Credentials are mandatory';
     END IF;
-    RETURN (input_config - 'credentials')::jsonb || user_mapping;
+    
+    -- For now, allow not passing username or password
+    IF input_config->'credentials'->'username' IS NOT NULL THEN
+        mapping := jsonb_build_object('user', input_config->'credentials'->'username');
+    END IF;
+    IF input_config->'credentials'->'password' IS NOT NULL THEN
+        mapping := mapping || jsonb_build_object('password', input_config->'credentials'->'password');
+    END IF;
+    
+    RETURN (input_config - 'credentials')::jsonb || jsonb_build_object('user_mapping', mapping);
 END
 $$
 LANGUAGE PLPGSQL IMMUTABLE PARALLEL SAFE;
@@ -154,6 +159,9 @@ DECLARE
     }';
     server_config jsonb;
 BEGIN
+    IF NOT (input_config ? 'server') THEN
+        RAISE EXCEPTION 'Server information is mandatory';
+    END IF;
     server_config := default_options || to_jsonb(input_config->'server');
     RETURN jsonb_set(input_config, '{server}'::text[], server_config);
 END
diff --git a/test/CDB_FederatedServer.sql b/test/CDB_FederatedServer.sql
index 58a033b..ffce997 100644
--- a/test/CDB_FederatedServer.sql
+++ b/test/CDB_FederatedServer.sql
@@ -71,15 +71,64 @@ SELECT '5.1', cartodb.CDB_Federated_Server_Unregister(server := 'doesNotExist'::
 SELECT '6.1', cartodb.CDB_Federated_Server_Unregister(server := 'myRemote2'::text);
 SELECT '6.2', cartodb.CDB_Federated_Server_List_Servers();
 
--- Should show the appropiate output (database, read-write, user, pass)
+-- Test empty config
+SELECT '7.1', cartodb.CDB_Federated_Server_Register_PG(server := 'empty'::text, config := '{}');
+-- Test without passing credentials
+SELECT '7.2', cartodb.CDB_Federated_Server_Register_PG(server := 'empty'::text, config := '{
+    "server": {
+        "dbname": "fdw_target",
+        "host": "localhost",
+        "port": @@PGPORT@@,
+        "extensions": "postgis",
+        "updatable": "false",
+        "use_remote_estimate": "true",
+        "fetch_size": "1000"
+    }
+}'::jsonb);
+-- Test with empty credentials
+SELECT '7.3', cartodb.CDB_Federated_Server_Register_PG(server := 'empty'::text, config := '{
+    "server": {
+        "dbname": "fdw_target",
+        "host": "localhost",
+        "port": @@PGPORT@@,
+        "extensions": "postgis",
+        "updatable": "false",
+        "use_remote_estimate": "true",
+        "fetch_size": "1000"
+    },
+    "credentials": { }
+}'::jsonb);
+SELECT '7.4', cartodb.CDB_Federated_Server_List_Servers();
+SELECT '7.5', cartodb.CDB_Federated_Server_Unregister(server := 'empty'::text);
+-- Test without without server options
+SELECT '7.6', cartodb.CDB_Federated_Server_Register_PG(server := 'empty'::text, config := '{
+    "credentials": {
+        "username": "other_remote_user",
+        "password": "foobarino"
+    }
+}'::jsonb);
 
--- Test multiple user mappings
+-- Should work ok with special characters
+SELECT '8.1', cartodb.CDB_Federated_Server_Register_PG(server := 'myRemote" or''not'::text, config := '{
+    "server": {
+        "dbname": "fdw target",
+        "host": "localhost",
+        "port": @@PGPORT@@,
+        "extensions": "postgis",
+        "updatable": "false",
+        "use_remote_estimate": "true",
+        "fetch_size": "1000"
+    },
+    "credentials": {
+        "username": "fdw user",
+        "password": "foo barino"
+    }
+}'::jsonb);
+SELECT '8.2', cartodb.CDB_Federated_Server_List_Servers();
+SELECT '8.3', cartodb.CDB_Federated_Server_Unregister(server := 'myRemote" or''not'::text);
 
--- Should work ok with special characters in the name
-
--- Should throw with invalid or NULL config
-
--- -- List works with multiple and single server
+-- Should throw when trying to unregistering a server that doesn't exists
+SELECT '8.4', cartodb.CDB_Federated_Server_Unregister(server := 'Does not exist'::text);
 
 -- Cleanup
 \set QUIET on
diff --git a/test/CDB_FederatedServer_expect b/test/CDB_FederatedServer_expect
index 24c6479..68972b1 100644
--- a/test/CDB_FederatedServer_expect
+++ b/test/CDB_FederatedServer_expect
@@ -11,3 +11,13 @@
 4.2|(myRemote2,postgres_fdw,localhost,5432,fdw_target,read-only,other_remote_user)
 ERROR:  Server "doesNotExist" does not exist
 6.1|
+ERROR:  Server information is mandatory
+ERROR:  Credentials are mandatory
+7.3|
+7.4|(empty,postgres_fdw,localhost,5432,fdw_target,read-only,)
+7.5|
+ERROR:  Server information is mandatory
+8.1|
+8.2|("myRemote"" or'not",postgres_fdw,localhost,5432,"fdw target",read-only,"fdw user")
+8.3|
+ERROR:  Server "Does not exist" does not exist