Tips for folks switching between DB2 and Oracle

Some Oracle and DB2 differences that are hard to find in the manuals:

Generic 1 row table for fast queries:
Oracle: dual
DB2: sysibm.sysdummy1

Current date and time for the server:
Oracle: select to_char(sysdate, 'yyyy-mm-dd hh24:mi:ss') from dual;
DB2: select current_time, current_date from sysibm.sysdummy1;

Delete a whole table, fast:
Oracle: truncate table x
DB2: load an empty file into the table