Some collations were causing IBMDB2I to report
inaccurate key range estimations to the optimizer
for LIKE clauses that select substrings. This can
be seen by running EXPLAIN. This problem primarily
affects multi-byte and unicode character sets.
This patch involves substantial changes to several
modules. There are a number of problems with the
character set and collation handling. These problems
have been or are being fixed, and a comprehensive
test has been included which should provide much
better coverage than there was before. This test
is enabled only for IBM i 6.1, because that version
has support for the greatest number of collations.
Modify plugins.m4 configuration framework so that plugins which are
not built still get added to the source distribution during make dist.
This came up now because we can only build ibmdb2i on i5/OS, and we
can't bootstrap our source dist on that platform. The solution is to
specify DIST_SUBDIRS containing all plugins, separate from SUBDIRS
which contains the plugins which are actually built.
This ibmdb2i code is from the ibmdb2i-ga3-src.zip file, with a patch
to plug.in to disable the plugin if the PASE environment isn't available.
