If two tables have multiple joins and one of them was compatible then
the incompatible join detection would fail.
This patch moves the incompatible join detection so that every join is
checked. It also removes the incompatible join detection from
expressionstep as this is redundant and was causing some valid quries to
fail.
pDictionaryScan won't work for BLOB/TEXT since it requires searching the
data file and rebuilding the token from matches. The tokens can't be
rebuild correctly due the bits in the token used for block counts. This
patch forces the use of pDictionaryStep instead for WHERE conditions.
In addition this patch adds support for TEXT/BLOB in various parts of
the job step processing. This fixes things like error 202 during an
UPDATE with a join condition on TEXT/BLOB columns.
