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M.S. wrote:

Hi

There's a paragraph in G. Wiorkowski's book (chapter 19) dedicated to
''fooling the optimizer' which contains some hints but she doesn't
recommend to foolish optimizer in this way. She says use 0=1 to discourage
the usage of a certain index or use OPTIMIZE FOR 1 ROW or some other trick
like 'hints'.

Personally I've never allowed manipulation of statistics in a production
environment (only 1 time actually, but it worked...)

According Dr. Pat Selinger the need to fool the optimizer was greatly
reduced in these last version of DB2.

Just an opinion

M.S.