mssql with transactions logs be truncated

[DerekHsueh]

Hi Everyone
1)
If "only once full backup" every day , Will the transactions logs be truncated?
Backup Exec 22.2 Administrator's Guide - English
https://sort.veritas.com/DocPortal/pdf/59226269-160534935-1
page-1094
If you want to run database backups only, instead of a mix of database and log backups, use the simple recovery model for the database so that the transaction log is automatically truncated when a checkpoint occurs in the database.

Via BE Administrator's Guide
I think : I have to use mix of database and log backups , If I hope to truncate transaction log.
Is it right ?

2)
SQL-specific backup methods：Automatic , Will the transactions logs be truncated?

Backup Exec 22.2 Administrator's Guide - English
https://sort.veritas.com/DocPortal/pdf/59226269-160534935-1
page-1099
■ Automatic - In addition, the databases that support log backups are backed up using the "Log backup" method.
■ Log - Back up and truncate transaction log.

Via BE Administrator's Guide
I think : If I choose the "Automatic" method, the BE will truncate mssql transaction log .
Just like "Log" method.
Is it right ?

Please give me some idea.
Thank you.

[pkh · Accepted solution]

If you use Simple Recovery Mode for your SQL Server databases, then there is essentially no logs kept.  This means that if there is failure, you can only recover up till the last good full backup of the database.

If you use logs, then you need to run a Log backup to backup the log and truncate them.

You use Automatic if your databases are a mixture of databases, in which some uses logs and some don't.  This makes it easier to setup your job, you just select all your databases.  Otherwise, you would need to select only those databases which uses logs when you run the Log backup.