SQL-92 basically specifies for a NOPAD collation that only space should
be ignored for matches. Tabs and other whitespace are handled
differently. We don't fully support collations yet so we assume the
defaults.
For TEXT columns (and some other scenarios) we don't do a DSS step to
scan dictionaries and do it directly in the BPS step instead. This patch
applies the previous fix to this case too.
For equality string matches other engines ignore trailing whitespace
(this does not apply to LIKE matches). So we should do the same. This
patch trims whitespace for MIN/MAX extent elimination checks, fixed
width columns and dictionary columns during equality matches against
constants (SELECT * FROM t1 WHERE b = 'ABC').
