return no rows
The algorithm of determining the best key for loose index scan is doing a loop
over the available indexes and selects the one that has the best cost.
It retrieves the parameters of the current index into a set of variables.
If the cost of using the current index is lower than the best cost so far it
copies these variables into another set of variables that contain the
information for the best index so far.
After having checked all the indexes it uses these variables (outside of the
index loop) to create the table read plan object instance.
The was a single omission : the key_infix/key_infix_len variables were used
outside of the loop without being preserved in the loop for the best index
so far.
This causes these variables to get overwritten by the next index(es) checked.
Fixed by adding variables to hold the data for the current index, passing
the new variables to the function that assigns values to them and copying
the new variables into the existing ones when selecting a new current best
index.
To avoid further such problems moved the declarations of the variables used
to keep information about the current index inside the loop's compound
statement.
In STRICT mode, out-of-bounds values caused an error message
to be queued (rather than just a warning), without any further
error-like processing happening. (The error is queued during
update, at which time it's too late. For it to be processed
properly, it would need to be queued during check-stage.)
The assertion rightfully complains that we're trying to send
an OK while having an error queued.
Changeset breaks a lot of tests out into check-stage. This also
allows us to send more correct warnings/error messages.
*with --with-charset=utf8*
Problem: wrong LONG TEXT field length is sent to a client
when multibyte server character set used.
Fix: always limit field length sent to a client to 2^32,
as we store it in 4 byte slot.
Note: mysql_client_test changed accordingly.
for bug #15936.
On some platforms fenv.h may #undef the min/max macros
defined in my_global.h.
Fixed by moving the #include directive for fenv.h from
mysqld.cc to my_global.h before definitions for min/max.
In STRICT mode, out-of-bounds values caused an error message
to be queued (rather than just a warning), without any further
error-like processing happening. (The error is queued during
update, at which time it's too late. For it to be processed
properly, it would need to be queued during check-stage.)
The assertion rightfully complains that we're trying to send
an OK while having an error queued.
Changeset breaks a lot of tests out into check-stage. This also
allows us to send more correct warnings/error messages.
Problem: storing "SELECT ... INTO @var ..." results in variables we used val_xxx()
methods which returned results of the current row.
So, in some cases (e.g. SELECT DISTINCT, GROUP BY or HAVING) we got data
from the first row of a new group (where we evaluate a clause) instead of
data from the last row of the previous group.
Fix: use val_xxx_result() counterparts to get proper results.
Bug#41112: crash in mysql_ha_close_table/get_lock_data with alter table
The problem is that the server wasn't handling robustly failures
to re-open a table during a HANDLER .. READ statement. If the
table needed to be re-opened due to it's storage engine being
altered to one that doesn't support HANDLER, a reference (dangling
pointer) to a closed table could be left in place and accessed in
later attempts to fetch from the table using the handler. Also,
if the server failed to set a error message if the re-open
failed. These problems could lead to server crashes or hangs.
The solution is to remove any references to a closed table and
to set a error if reopening a table during a HANDLER .. READ
statement fails.
Bug#41112: crash in mysql_ha_close_table/get_lock_data with alter table
The problem is that the server wasn't handling robustly failures
to re-open a table during a HANDLER .. READ statement. If the
table needed to be re-opened due to it's storage engine being
altered to one that doesn't support HANDLER, a reference (dangling
pointer) to a closed table could be left in place and accessed in
later attempts to fetch from the table using the handler. Also,
if the server failed to set a error message if the re-open
failed. These problems could lead to server crashes or hangs.
The solution is to remove any references to a closed table and
to set a error if reopening a table during a HANDLER .. READ
statement fails.
There is no test case in this change set as the test depends on
a testing feature only available on 5.1 and later.
- Add support for setting it as a server commandline argument
- Add support for those switches:
= no_index_merge
= no_index_merge_union
= no_index_merge_sort_union
= no_index_merge_intersection
Both of our own implementations of rint(3) were inconsistent with the
most common behavior of rint() on those platforms that have it: round
to nearest, break ties by rounding to nearest even.
Fixed by leaving just one implementation of rint() in our source tree,
and changing its behavior to match the most common native
implementations on other platforms.
slave.
In mixed mode, if we create a temporary table and do some update which switch to ROW format,
the format will keep in ROW format until the session ends or the table is dropped explicitly.
When the session ends, the temp table is dropped automaticly at cleanup time.
but it checks only current binlog format and so skip insertion of DROP TABLE instructions into binlog.
So the temp table can't be dropped correctly at slave.
Our solution is that when closing temp tables at cleanup time we check both binlog format and binlog mode,
and we could write DROP TABLE instructions into binlog if current binlog format is ROW but in MIX mode.
If secure-file-priv was set on slave, it became unable to execute
LOAD DATA INFILE statements sent from master using mixed or
statement-based replication.
This patch fixes the issue by ignoring this security restriction
and checking if the files are created and read by the slave in the
--slave-load-tmpdir while executing the SQL Thread.
Signed integer format specifier forced to print the binlog header with server_id
negative if the unsigned value sets the sign-bit ON.
Fixed with correcting the specifier to correspond to typeof(server_id) == ulong.
The problem is that select queries executed concurrently with
a concurrent insert on a MyISAM table could be cached if the
select started after the query cache invalidation but before
the unlock of tables performed by the concurrent insert. This
race could happen because the concurrent insert was failing
to prevent cache of select queries happening at the same time.
The solution is to add a 'uncacheable' status flag to signal
that a concurrent insert is being performed on the table and
that queries executing at the same time shouldn't cache the
results.
connections
The problem is that tables can enter open table cache for a thread without
being properly cleaned up. This can happen if make_join_statistics() fails
to read a const table because of e.g. a deadlock. It does set a member of
TABLE structure to a value it allocates, but doesn't clean-up this setting
on error nor does it set the rest of the members in JOIN to allow for
automatic cleanup.
As a result when such an error occurs and the next statement depends re-uses
the table from the open tables cache it will get it with this
TABLE::reginfo.join_tab pointing to a memory area that's freed.
Fixed by making sure make_join_statistics() cleans up TABLE::reginfo.join_tab
on error.
