Fully qualify function calls

scripts-available/CDB_ColumnNames.sql

@@ -1,5 +1,5 @@
 -- Function returning the column names of a table
-CREATE OR REPLACE FUNCTION CDB_ColumnNames(REGCLASS)
+CREATE OR REPLACE FUNCTION @extschema@.CDB_ColumnNames(REGCLASS)
 RETURNS SETOF information_schema.sql_identifier
 AS $$
   SELECT
@@ -13,4 +13,4 @@ $$ LANGUAGE SQL STABLE PARALLEL SAFE;
 
 -- This is to migrate from pre-0.2.0 version
 -- See http://github.com/CartoDB/cartodb-postgresql/issues/36
-GRANT EXECUTE ON FUNCTION CDB_ColumnNames(REGCLASS) TO PUBLIC;
+GRANT EXECUTE ON FUNCTION @extschema@.CDB_ColumnNames(REGCLASS) TO PUBLIC;