Shamelessly stolen:

Yesterday
All those backups seemed a waste of pay.
Now my database has gone away.
Oh I believe in yesterday.

Suddenly,
There's not half the files there used to be,
And there's a milestone hanging over me
The system crashed so suddenly.

I pushed something wrong
What it was I could not say.
Now all my data's gone away
and I long for yesterday-ay-ay-ay.

Yesterday,
The need for back-ups seemed so far away.
I knew my data was all here to stay,
Now I believe in yesterday.