What is a self-join and how is it used?
What will be an ideal response?
A self-join is a join of one table to itself. This is often used for unary relationships where you have a recursive foreign key. One possible use for this would be to produce a list of who is supervised by another staff member. Self-joins can be slow, so they should be used with caution.
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A major recommendation for combating sexual harassment is to
A) post any sexually-toned comments you hear on the company Web site. B) keep a running log of incidents against you. C) embarrass anyone who tells a sexually-oriented joke by posting his or her photo and the comment on a blog. D) wear a button that says, "Not me, not now."
What is the EMV for Option 2 in the following decision table?
States of Nature Alternatives S1 S2 p .6 .4 Option 1 200 300 Option 2 50 350 A) 50 B) 100 C) 170 D) 200 E) 350