Is it possible to get average log backup size?

[cwbrumett]

I need to capture some database growth stats for a hardware purchase. I'm currently doing backup with weekly fulls, daily diffs, and t logs every 15 mins.

I was thinking I could get an average of my t log backups to figure out future growth.

thanks for any help.

 

[cwbrumett]

found it ... for anyone else that reads this.

SELECT 
   CONVERT(CHAR(100), SERVERPROPERTY('Servername')) AS Server,
   msdb.dbo.backupset.database_name, 
   msdb.dbo.backupset.backup_start_date, 
   msdb.dbo.backupset.backup_finish_date,
   CASE msdb..backupset.type 
       WHEN 'D' THEN 'Database' 
       WHEN 'L' THEN 'Log' 
   END AS backup_type, 
   msdb.dbo.backupset.backup_size, 
    convert (decimal(30,2), (msdb.dbo.backupset.backup_size + 1536) / 1024) As SizeInKB,
    convert (decimal(30,2), (msdb.dbo.backupset.backup_size + 1536) / 1024 / 1024) As SizeInMBs,
    convert (decimal(7,3), (msdb.dbo.backupset.backup_size + 1536) /1024 / 1024 / 1024) As SizeInGBs

FROM   msdb.dbo.backupmediafamily 
   INNER JOIN msdb.dbo.backupset ON msdb.dbo.backupmediafamily.media_set_id = msdb.dbo.backupset.media_set_id 

WHERE  
	--pull only last 90 days
	(CONVERT(datetime, msdb.dbo.backupset.backup_start_date, 102) >= GETDATE() - 90) 
	--only want logs
	AND msdb..backupset.type = 'L'

ORDER BY 
   msdb.dbo.backupset.database_name,
   msdb.dbo.backupset.backup_finish_date