John did try to lead you there. I'm trying to give you what I think is a better way to measure what you are trying to measure. In a properly managed SQL Server, database files should never grow automatically, the DBA should be monitoring the space used and free space in database files and manually grow the files during a maintenance window or low usage time before an autogrow needs to happen. The scripts I provided can help you monitor space used and free space AND show you how much database files have grown when autogrows take place.

Here's the code John was trying to lead you to:

WITH dbSizes AS

(

SELECT

*, /* replace this with your desired column list */

/* ordering DESC means the most recent row will be 1 */

ROW_NUMBER() OVER (PARTITION BY name ORDER BY DataLogged DESC) AS rowNo

FROM

databaseSizes

)

SELECT

*, /* replace this with your desired column list */

(A.DataFileSizeGB - B.DataFileSizeGB)/1024.0 AS DataFileSizeChangeInMB,

(A.LogFileSizeGB - B.LogFileSizeGB)/1024.0 AS LogFileSizeChangeInMB

FROM

dbSizes AS A

LEFT JOIN dbSizes AS B

ON A.name = B.name AND

/* A has the most recent row (1) so it needs to be B - 1 to match */

A.rowNo = B.rowNo - 1