a. If a person leaves a company, we can transfer his/records to others using data loader.
    b. If we want to add products for multiple currencies, we go for data loader.
    c. If we want to delete the test data, we go for data loader.
    d. If we want to handle more than 50000 records.
   
2. How much time will it take for loading contacts,leads,accounts,opportunities etc?Which one will get more time for loading?

It is based on the triggers, validation rules, etc behind the objects.

Usually it will take more time on Opportunity.



3. What are the most common problems you faced in loading data?

    a. Uploading multilanguage data.
    b. Fault string error.
    c. Locking Errors

4. Why exactly the batch apex is used in your project?

    a. Background process
    b. Reminder settings
    c. Daily or weekly activities which will handle more records.
   
5. When actually sandbox is moved to production,when i want to change the some part of code,how can you manage to restrict the previous code not to get executed?

Using eclipse, we have to open the xml of the class and we have to change “Active” to “Inactive” in status tag.

Example: <status>Inactive</status>