To improve performance, you can use the optimize database command to rebuild or reorganize indexes based on the fragmentation in the indexes of tables. It is recommended that you should execute the optimize command after performing large transactions such as importing a huge database, cloning a database, importing huge models, and also after performing backup and restore operations on a database.

You can optimize a database by using one of the following tools:

For more information about transaction logs, refer to the following help topic for SQL Server:

The Transaction Log

https://docs.microsoft.com/sql/relational-databases/logs/the-transaction-log-sql-server?view=sql-server-2017