However, the rest of the phone sucks, so I can't recommend it.
I use my phone right now for sshing into my home machines and getting analytics, benchmarks, error logs, making spot changes to files, editing users and groups, etc. If you have a smartphone with a foldout keyboard, you're set. The possibility of me being able to do this with urxvt and emacs running on the phone is just awesome. Interacting with postgres on the cli with my phone is a dream as well. Obviously writing out huge statements is a pain, but you're generally just running one liners through to find some info.
unless you meant an actual bluetooth keyboard, then its just a matter of foldable vs fixed and what you like more. My dad uses this:
http://www.quill.com/android-keyboards/cbs/283296.html?cm_mm...
for his nexus 7. Works out pretty well.
Honestly? No. I can't imagine the agony of trying to type out a SQL query on my phone. I have a Macbook Air, which is light enough for me to carry around with me the vast majority of the time- it's great.
If I wanted something smaller I would perhaps get a tablet with a keyboard (or a netbook, if they weren't all terrible)... but doing any meaningful work on my phone? No thanks. I can barely bring myself to type out a reasonably-sized e-mail on mine.