a) you can change the recovery mode of your database to simple. ( I think it is full now ) BUT IT IS NOT ADVISABLE TO CHANGE THIS. In case of a data recovery you will not be able to recover if you have a simple recovery method.
b) yes you can.
Deatatch Db
Delete Log
Attach Mdf file .
( I have bad expereces on this when there are multiple log files in database)
Also , you can have Backup NO LOG
BACKUP LOG AdventureWorks WITH NO_LOG;
This is absolutely not recommended because it breaks the log chain, the series of log backups from which you would recover your database to a point in time. Microsoft recommends running a full backup immediately after using this statement.
c) Put this command in job and schedule it
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