Here's some excerpts from it, leaving the rest for reading...
"DUAL is owned by SYS. SYS owns the data dictionary,More
therefore DUAL is part of the data dictionary. You are not to modify the data dictionary
via SQL ever -- wierd things can and will happen"
the optimizer understands dual is a magic, special 1 row table. It stopped on theRead the rest of article here...
select * because there is to be one row in there. Its just the way it works.
Ask Tom "All about the DUAL table "
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