Simple Recovery Model, Sql Server 2012 Express
I allocate one database for every six months, steadily grows to about 7 Gigs. (About 1.3 gigs of growth per month). This morning I did a full backup and havent' added or edited any records since then. A moment ago I decided to do a differential (just
so I could learn the syntax). I expected the differential to be near-zero bytes in size. Instead I got a file almost 2 gigs in size (although Winzip shrunk it to 1/4 gig).
Why such a large differential given that I did a full backup this morning? Admittedly I put the differntial in a different directory than the full backup - was that the problem? (Incidentally I hear that the With Compression option is unavailable for Express
Edition).
Here's my script for the differential.
BACKUP DATABASE Year2014_835_1_v2 TO DISK='C:\Debug\Zplay1.diff' WITH DIFFERENTIAL, INIT, CHECKSUM
The full backup wasn't by script, however - I used SSMS and it produced a file about 7 gigs in size.
And here's the output from the differential script:
"Processed 231840 pages for database 'Year2014_835_1_v2', file 'Year2014_835_1_v2' on file 1.
Processed 4 pages for database 'Year2014_835_1_v2', file 'Year2014_835_1_v2_log' on file 1.
BACKUP DATABASE WITH DIFFERENTIAL successfully processed 231844 pages in 50.484 seconds (35.878 MB/sec).