When there are no underlying tables specified for a merge table,
SHOW CREATE TABLE outputs a statement that cannot be executed. The
same is true for mysqldump (it generates dumps that cannot be
executed).
This happens because SQL parser does not accept empty UNION() clause.
This patch changes the following:
- it is now possible to execute CREATE/ALTER statement with
empty UNION() clause.
- the same as above, but still worth noting: it is now possible to
remove underlying tables mapping using ALTER TABLE ... UNION=().
- SHOW CREATE TABLE does not output UNION() clause if there are
no underlying tables specified for a merge table. This makes
mysqldump slightly smaller.
using a trig in SP
For all 5.0 and up to 5.1.12 exclusive, when a stored routine or
trigger caused an INSERT into an AUTO_INCREMENT column, the
generated AUTO_INCREMENT value should not be written into the
binary log, which means if a statement does not generate
AUTO_INCREMENT value itself, there will be no Intvar event (SET
INSERT_ID) associated with it even if one of the stored routine
or trigger caused generation of such a value. And meanwhile, when
executing a stored routine or trigger, it would ignore the
INSERT_ID value even if there is a INSERT_ID value available set
by a SET INSERT_ID statement.
Starting from MySQL 5.1.12, the generated AUTO_INCREMENT value is
written into the binary log, and the value will be used if
available when executing the stored routine or trigger.
Prior fix of this bug in MySQL 5.0 and prior MySQL 5.1.12
(referenced as the buggy versions in the text below), when a
statement that generates AUTO_INCREMENT value by the top
statement was executed in the body of a SP, all statements in the
SP after this statement would be treated as if they had generated
AUTO_INCREMENT by the top statement. When a statement that did
not generate AUTO_INCREMENT value by the top statement but by a
function/trigger called by it, an erroneous Intvar event would be
associated with the statement, this erroneous INSERT_ID value
wouldn't cause problem when replicating between masters and
slaves of 5.0.x or prior 5.1.12, because the erroneous INSERT_ID
value was not used when executing functions/triggers. But when
replicating from buggy versions to 5.1.12 or newer, which will
use the INSERT_ID value in functions/triggers, the erroneous
value will be used, which would cause duplicate entry error and
cause the slave to stop.
The patch for 5.1 fixed it to ignore the SET INSERT_ID value when
executing functions/triggers if it is replicating from a master
of buggy versions, another patch for 5.0 fixed it not to generate
the erroneous Intvar event.
using a trig in SP
For all 5.0 and up to 5.1.12 exclusive, when a stored routine or
trigger caused an INSERT into an AUTO_INCREMENT column, the
generated AUTO_INCREMENT value should not be written into the
binary log, which means if a statement does not generate
AUTO_INCREMENT value itself, there will be no Intvar event (SET
INSERT_ID) associated with it even if one of the stored routine
or trigger caused generation of such a value. And meanwhile, when
executing a stored routine or trigger, it would ignore the
INSERT_ID value even if there is a INSERT_ID value available set
by a SET INSERT_ID statement.
Starting from MySQL 5.1.12, the generated AUTO_INCREMENT value is
written into the binary log, and the value will be used if
available when executing the stored routine or trigger.
Prior fix of this bug in MySQL 5.0 and prior MySQL 5.1.12
(referenced as the buggy versions in the text below), when a
statement that generates AUTO_INCREMENT value by the top
statement was executed in the body of a SP, all statements in the
SP after this statement would be treated as if they had generated
AUTO_INCREMENT by the top statement. When a statement that did
not generate AUTO_INCREMENT value by the top statement but by a
function/trigger called by it, an erroneous Intvar event would be
associated with the statement, this erroneous INSERT_ID value
wouldn't cause problem when replicating between masters and
slaves of 5.0.x or prior 5.1.12, because the erroneous INSERT_ID
value was not used when executing functions/triggers. But when
replicating from buggy versions to 5.1.12 or newer, which will
use the INSERT_ID value in functions/triggers, the erroneous
value will be used, which would cause duplicate entry error and
cause the slave to stop.
The patch for 5.0 fixed it not to generate the erroneous Intvar
event, another patch for 5.1 fixed it to ignore the SET INSERT_ID
value when executing functions/triggers if it is replicating from
a master of buggy versions.
When concurrent inserts were disabled, statements after an INSERT
were not put into the query cache. This happened because we do not
save the current data file length at statement start when
concurrent inserts are disabled. But we checked the always zero
local length against the real file length anyway.
Fixed by doing the check only if concurrent inserts are not diabled.
table with backticks
(Thanks to Lu Jingdong, though I did not take his patch directly, as
it contained a significant flaw.)
It wasn't a backtick/parsing problem. We merely didn't anticipate
and allocate enough space to handle the optional "#mysql50#" table-
name prefix.
Now, allocate that extra space in case we need it when we look up
a legacy table to get its file's name.
than max_connections -- which results in user lockout.
The problem was that the variable thread_count that contains
the number of active threads was interpreted as a number of
active connections.
The fix is to introduce a new counter for active connections.
In cases when TRUNCATE was executed by invoking mysql_delete() rather
than by table recreation (for example, when TRUNCATE was issued on
InnoDB table with is referenced by foreign key) triggers were invoked.
In debug builds this also led to crash because of an assertion, which
assumes that some preliminary actions take place before trigger
invocation, which doesn't happen in case of TRUNCATE.
The fix is not to execute triggers in mysql_delete() when this
function is used by TRUNCATE.
Problem: if the IO slave thread is attempting to connect,
STOP SLAVE waits for the attempt to finish.
It may take a long time.
Fix: don't wait, stop the slave immediately.
WHERE f1 < n ignored row if f1 was indexed integer column and
f1 = TYPE_MAX ^ n = TYPE_MAX+1. The latter value when treated
as TYPE overflowed (obviously). This was not handled, it is now.
m_status == DA_OK
Reading from information_scema.tables or information_schema.columns
may cause assertion failure in debug builds. This may happen under
rare circumstances when information_schema fails to get information
about a table (e.g. when a connection is killed).
This happens because open_normal_and_derived_tables() can return an
error without setting an error message in THD. But information_schema
attempts to get an error message from THD unconditionally.
With this fix information_schema attempts to get an error message
from THD only in case error message is set in THD.
Problem: in mixed and statement mode, a query that refers to a
system variable will use the slave's value when replayed on
slave. So if the value of a system variable is inserted into a
table, the slave will differ from the master.
Fix: mark statements that refer to a system variable as "unsafe",
meaning they will be replicated by row in mixed mode and produce a warning
in statement mode. There are some exceptions: some variables are actually
replicated. Those should *not* be marked as unsafe.
BUG#34732: mysqlbinlog does not print default values for auto_increment variables
Problem: mysqlbinlog does not print default values for some variables,
including auto_increment_increment and others. So if a client executing
the output of mysqlbinlog has different default values, replication will
be wrong.
Fix: Always print default values for all variables that are replicated.
I need to fix the two bugs at the same time, because the test cases would
fail if I only fixed one of them.
MYSQL_TYPE_NEWDECIMAL
Added support for the type MYSQL_TYPE_NEWDECIMAL. It now works like
MYSQL_TYPE_DECIMAL. Unfortunately there cannot be a test case until
we have a working information_schema plugin as part of the source
distribution.
There was a failure in that show slave status displayed a wrong message
when slave stopped at processing a row event inserting to a default-less
column.
The problem seem to have ceased after recent fixes in rbr code.
However, the test was not updated to carry testing of the case commented-out.
Uncommenting and editing the test.
Notice, Bug#23907 is most probably a duplicate of this one.
returns wrong results
Casting AVG() to DECIMAL led to incorrect results when the arguments
had a non-DECIMAL type, because in this case
Item_sum_avg::val_decimal() performed the division by the number of
arguments twice.
Fixed by changing Item_sum_avg::val_decimal() to not rely on
Item_sum_sum::val_decimal(), i.e. calculate sum and divide using
DECIMAL arithmetics for DECIMAL arguments, and utilize val_real() with
subsequent conversion to DECIMAL otherwise.
