After merge fix. MyISAM version 10.

into  chilla.local:/home/mydev/mysql-5.0-bug8283

into  chilla.local:/home/mydev/mysql-4.1-bug8283-one

OPTIMIZE TABLE with myisam_repair_threads > 1 performs a non-quick 
parallel repair. This means that it does not only rebuild all 
indexes, but also the data file.

Non-quick parallel repair works so that there is one thread per 
index. The first of the threads rebuilds also the new data file.

The problem was that all threads shared the read io cache on the
old data file. If there were holes (deleted records) in the table,
the first thread skipped them, writing only contiguous, non-deleted
records to the new data file. Then it built the new index so that
its entries pointed to the correct record positions. But the other
threads didn't know the new record positions, but put the positions
from the old data file into the index.

The new design is so that there is a shared io cache which is filled
by the first thread (the data file writer) with the new contiguous
records and read by the other threads. Now they know the new record
positions.

Another problem was that for the parallel repair of compressed
tables a common bit_buff and rec_buff was used. I changed it so
that thread specific buffers are used for parallel repair.

A similar problem existed for checksum calculation. I made this
multi-thread safe too.

into  mysql.com:/home/svoj/devel/mysql/BUG22937/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG22937/mysql-4.1-engines

This is addition to fix for bug21617. Valgrind reports an error when
opening merge table that has underlying tables with less indexes than
in a merge table itself.

Copy at most min(file->keys, table->key_parts) elements from rec_per_key array.
This fixes problems when merge table and subtables have different number of keys.

into  mysql.com:/home/svoj/devel/mysql/BUG21381/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG10974/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG21381/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG21381/mysql-4.1-engines

Though this is not storage engine specific problem, I was able to
repeat this problem with BDB and NDB engines only. That was the
reason to add a test case into ndb_update.test. As a result
different bad things could happen.

BDB has removed duplicate rows which is not expected.
NDB returns an error.

For multi table update notify storage engine about UPDATE IGNORE
as it is done in single table UPDATE.

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-4.1-engines

into  mysql.com:/home/svoj/devel/mysql/merge/mysql-4.1-engines

into  chilla.local:/home/mydev/mysql-4.0-bug20719

into  chilla.local:/home/mydev/mysql-5.0-bug20627

into  mysql.com:/home/svoj/devel/mysql/engines/mysql-5.0-engines

Was introduced with patch for bug#21675.

into  chilla.local:/home/mydev/mysql-5.0-bug20627

into  chilla.local:/home/mydev/mysql-4.1-bug22384

into  mysql.com:/home/svoj/devel/mysql/engines/mysql-5.0-engines

into  chilla.local:/home/mydev/mysql-5.0-bug22384

  After merge fix

into  moonbone.local:/work/5505-bug-5.0-opt-mysql

On an INSERT into an updatable but non-insertable view an error message was
issued stating the view being not updatable. This can lead to a confusion of a
user.

A new error message is introduced. Is is showed when a user tries to insert
into a non-insertable view.

into  chilla.local:/home/mydev/mysql-5.0-bug22384

into  chilla.local:/home/mydev/mysql-4.1-bug22384

into  mysql.com:/home/svoj/devel/mysql/BUG21617/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG21617/mysql-4.1-engines

Crash may happen when selecting from a merge table that has underlying
tables with less indexes than in a merge table itself.

If number of keys in merge table is not bigger than requested key number,
return error.

into  mysql.com:/home/svoj/devel/mysql/BUG21675/mysql-5.0-engines

into  mysql.com:/home/svoj/devel/mysql/BUG21675/mysql-5.0-engines

If mysqld is linked against system installed zlib (which is likely compiled w/o
LFS) and archive table exceedes 2G, mysqld will likely be terminated with SIGXFSZ.

Prior to actual write perform a check if there is space in data file. This fixes
abnormal process termination with SIGXFSZ.

No test case for this bugfix.