The topic describes the EX0011 analysis rule.
The rule checks for indexes that haven't been used recently and are possible candidates to be dropped.
The rule uses the SQL Server Dynamic Management Views to get index usage information.
The unused indexes information is based on statistics gathered since the last time SQL Server instance was started.
Be careful when dropping unused or rarely used indexes. Some indexes can be used rarely and be created for specific purpose; for example, to optimize monthly report.
The parameter specifies the efficiency of the index since the last server restart. The index efficiency is calculated based on the reads per writes.
Indexes covering less rows than specified by this parameter will be ignored.