For "count(*) while index_column = value" an index read
is done. It consists of an index scan and retrieval of
each key.
For efficiency reasons the index scan stores the key in
the special buffer 'lastkey2' once only. At the first
iteration it notes this fact with the flag
HA_STATE_RNEXT_SAME in 'info->update'.
For efficiency reasons, the key retrieval for blobs
does not allocate a new buffer, but uses 'lastkey2'...
Now I clear the HA_STATE_RNEXT_SAME flag whenever the
buffer has been polluted. In this case, the index scan
copies the key value again (and sets the flag again).
when high concurrency": remove HASH::current_record and make it
an external search parameter, so that it can not be the cause of a
race condition under high concurrent load.
The bug was in a race condition in table_hash_search,
when column_priv_hash.current_record was overwritten simultaneously
by multiple threads, causing the search for a suitable grant record
to fail.
No test case as the bug is repeatable only under concurrent load.
into parts when converting to Unicode.
m_ctype.h:
Reorganizing mb_wc return codes to be able
to return "an unassigned N-byte-long character".
sql_string.cc:
Adding code to detect and properly handle
unassigned characters (i.e. the those character
which are correctly formed according to the
character specifications, but don't have Unicode
mapping).
Many files:
Fixing conversion function to return new codes.
ctype_ujis.test, ctype_gbk.test, ctype_big5.test:
Adding a test case.
ctype_ujis.result, ctype_gbk.result, ctype_big5.result:
Fixing results accordingly.
Two handler objects were present, one was used for an insert and the other for a select
The state of the statistics was local to the handler object and thus the other handler
object didn't notice the insert.
Fix included:
1) Add a new variable key_stat_version added to whenever statistics was considered in need
of update (previously key_stats_ok= FALSE in those places)
2) Add a new handler variable key_stat_version assigned whenever key_stats_ok= TRUE was set
previously
3) Fix records_in_range to return records if records <= 1
4) Fix records_in_range to add 2 to rec_per_key to ensure we don't specify 0 or 1 when it isn't
and thus invoking incorrect optimisations.
5) Fix unique key handling for HEAP table in records_in_range
1. it's wrong to use memcpy() for overlapped areas;
2. we use it only once.
During merge to 4.1 will remove a memcpy_overlap() call
from strings/ctype-tis620.c as well in order to fix
bug #10836: ctype_tis620 test failure with ICC-compiled binaries on IA64.
In cp932, '\' character can be the second byte in a
multi-byte character stream. This makes it difficult to use
mysql_escape_string. Added flag to indicate which languages allow
'\' as second byte of multibyte sequence so that when putting a prepared
statement into the binlog we can decide at runtime whether hex encoding
is really needed.
