Which of the following is NOT a variant of time stamp-based method of concurrency control in database management system?

Option 1 is correct

Concept

There are three basic type of timestamp-based methods of concurrency control: 

• Total timestamp ordering
• Partial timestamp ordering
• Multiversion timestamp ordering

Additional Information 

• Total timestamp ordering : 

• Partial timestamp ordering :

• Multiversion Timestamp ordering : 

it stores several versions of an updated data, allowing transactions to see a consistent set of versions for all data it accesses.  So, it reduces the conflicts that result in transaction restarts to those where there is a  Write-Write conflict.