well, i'm only being half-serious here :0)
if you're using Oracle as a back-end :

select to_char(sysdate,'YYYY-MM-DD HH:MI:SS') from dual;
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if you're using SQL Server , then it's even shorter :

select getdate()
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can't get shorter than that, can u ? ;-)
(I wouldnt recommend firing an sql query just to get the timestamp, though)