# Incompatibilities

MySQL Native Driver is in most cases compatible with MySQL Client Library (`libmysql`). This section documents incompatibilities between these libraries.

- Values of `bit` data type are returned as binary strings (e.g. "\0" or "\x1F") with `libmysql` and as decimal strings (e.g. "0" or "31") with `mysqlnd`. If you want the code to be compatible with both libraries then always return bit fields as numbers from MySQL with a query like this: `SELECT bit + 0 FROM table`.