src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@Override
    public String create(String json, boolean autoCommit) throws SQLException, IOException {
        return update(null, json, autoCommit);
    }
@Override
    public String create(String json, boolean autoCommit) throws SQLException, IOException {
        return update(null, json, autoCommit);
    }
Create a new entity in the database from the provided JSON string. Note, any call to create or update must provide
a JSON string with the full set of fields matching the definition of the GTFS table in the Table class.