We are trying to restore the customization fields from MYSQL database backup file but we are unable to restore customized field data.We got our other data i.e. contacts, accouts email settings etc.
I am not sure if I understand the problem correctly. You are trying to restore a complete database backup (MySQL or MSSQL?)?
If you have custom fields, the values of those are normally not stored in the main table, but in the _cstm table (for example main table is "accounts" then the table for the custom fields would be "accounts_cstm").
Retrieving data ...