We have developed a software that uses,MySQL database,and after some month of usage,some of the database tables had been corrupted and need to be repaired,what is the cause of this corruption? How can we fix them? How can we prevent the database tables from corruption. Because of the corruption,we are not able to create a backup using Navicat,and we can not generate a dump too. Is that possible to fix this tables using MySQL engine,and some of this corruption is about empty fields in database tables.