All programmers who often work with MySQL databases have suffered the undesireable experience of having some of those databases damaged or corrupted, making access impossible.
For this specific case there is Recovery for MySQL, which can repair and restore (wherever possible) these MySQL databases (it works with all the versions of MySQL, including 5.0) working with MYD and MYI file extensions. Once the data is restored, the program generates sentences in SQL so you can reinsert them.
Recovery for MySQL not only recovers data, but also restores the structure of the tables, indices, etc.