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.
wmemset was being used to fill the row buffers.
wmemset was intended to fill the buffer with
16-bit UCS2 pad values. However, the 64-bit
version of wmemset uses 32-bit wide characters
and thus filled the buffer incorrectly. In some
cases, the null byte map would be overwritten,
causing ctype_utf8.test and ibmdb2i_rir.test to
fail, giving the error message CPF5035.
This patch eliminates the use of wmemset to fill
the row buffer. wmemset has been replaced with
memset16, which always fills memory with 16-bit
values.
When a user selected an unsupported character set for an
IBMDB2I table, error 2501 or 2511 may have been returned,
giving the appearance of an internal programming error.
This patch consolidates these errors into a single descriptive
error message for the common case of an unsupported character
set.
The new error number is 2504 and indicates a user error.
The errors 2501 and 2511 remain to indicate cases of internal
programming errors.
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.
