on re-execution of prepared statement
Problem: some (see eq_ref_table()) ORDER BY/GROUP BY optimization
is called before each PS execution. However, we don't properly
initialize its stucture every time before the call.
Fix: properly initialize the sturture used.
The problem is a somewhat common misusage of the strmake function.
The strmake(dst, src, len) function writes at most /len/ bytes to
the string pointed to by src, not including the trailing null byte.
Hence, if /len/ is the exact length of the destination buffer, a
one byte buffer overflow can occur if the length of the source
string is equal to or greater than /len/.
The test allowed random coincidence of connection ids for two concurrent
sessions performing CREATE/DROP temp tables.
Fixed with correcting the test. The sessions connection ids are not changed
from their defaults anymore.
When compressed myisam files are opened, they are always memory mapped
sometimes causing memory swapping problems.
When we mmap the myisam compressed tables of size greater than the memory
available, the kswapd0 process utilization is very high consuming 30-40% of
the cpu. This happens only with linux kernels older than 2.6.9
With newer linux kernels, we don't have this problem of high cpu consumption
and this option may not be required.
The option 'myisam_mmap_size' is added to limit the amount of memory used for
memory mapping of myisam files. This option is not dynamic.
The default value on 32 bit system is 4294967295 bytes and on 64 bit system it
is 18446744073709547520 bytes.
Note: Testcase only tests the option variable. The actual bug has be to
tested manually.
Problem: inserting a record we don't set unused null bits in the
record buffer if no default field values used.
That may lead to wrong live checksum calculation.
Fix: set unused null bits in the record buffer in such cases.
int join_read_key(JOIN_TAB*)
The eq_ref access method TABLE_REF (accessed through
JOIN_TAB) to save state and to track if this is the
first row it finds or not.
This state was not reset on subquery re-execution
causing an assert.
Fixed by resetting the state before the subquery
re-execution.
5.0 buffer overflow for ER_UPDATE_INFO, or truncated info message in 5.1
5.0.86 has a buffer overflow/crash, and 5.1.40 has a truncated message.
errmsg.txt contains this:
ER_UPDATE_INFO
rum "Linii identificate (matched): %ld Schimbate: %ld Atentionari
(warnings): %ld"
When that is sprintf'd into a buffer of STRING_BUFFER_USUAL_SIZE size,
a buffer overflow can happen.
The solution to this is to use MYSQL_ERRMSG_SIZE for the buffer size,
instead of STRING_BUFFER_USUAL_SIZE. This will allow longer strings.
To avoid potential crashes, we will also use my_snprintf instead of
sprintf.
The help text for --init-slave=name:
"Command(s) that are executed when a slave connects to this master".
This text indicate that the --init-slave option is set on a master
server, and the master server passes the option's argument to slave
which connects to it. This is wrong. Actually the --init-slave option
just can be set on a slave server, and then the slave server executes
the argument each time the SQL thread starts.
Correct the help text for --init-slave option as following:
"Command(s) that are executed by a slave server each time the SQL thread starts."
SPATIAL and FULLTEXT indexes don't support algorithm
selection.
Disabled by creating a special grammar rule for these
in the parser.
Added some encasulation of duplicate parser code.
Part 2 :
There was a special optimization on the ref access method for
ORDER BY ... DESC that was set without actually looking on the type of the
selected index for ORDER BY.
Fixed the SELECT ... ORDER BY .. DESC (it uses a different code path compared
to the ASC that has been fixed with the previous fix).
There are three issues that caused rpl_killed_ddl fails sporadically
in pb2:
1) thd->clear_error() was not called before create Query event
if operation is executed successfully.
2) DATABASE d2 might do exist because the statement to CREATE or
ALTER it was killed
3) because of bug 43353, kill the query that do DROP FUNCTION or
DROP PROCEDURE can result in SP not found
This patch fixed all above issues by:
1) Called thd->clear_error() if the operation succeeded.
2) Add IF EXISTS to the DROP DATABASE d2 statement
3) Temporarily disabled testing DROP FUNCTION/PROCEDURE IF EXISTS.
solaris after a crash
This patch adds a Solaris-specific version of
print_stacktrace() which uses printstack(2), available on all
Solaris versions since Solaris 9. (While Solaris 11 adds
support for the glibc functions backtrace_*() as of
PSARC/2007/162, printstack() is used for consistency over all
Solaris versions.)
The symbol names are mangled, so use of c++filt may be
required as described in the MySQL documentation.
field='const1' AND field='const2' in some cases
Building multiple equality predicates containing
a constant which is compared as a datetime (with a field)
we should take this fact into account and compare the
constant with another possible constatns as datetimes
as well.
E.g. for the
SELECT ... WHERE a='2001-01-01' AND a='2001-01-01 00:00:00'
we should compare '2001-01-01' with '2001-01-01 00:00:00' as
datetimes but not as strings.
Actually there is two different bugs.
The first one caused crash on queries with WHERE condition over views
containing WHERE condition. A wrong check for prepared statement phase led
to items for view fields being allocated in the execution memory and freed
at the end of execution. Thus the optimized WHERE condition refers to
unallocated memory on the second execution and server crashed.
The second one caused by the Item_cond::compile function not saving changes
it made to the item tree. Thus on the next execution changes weren't
reverted and server crashed on dereferencing of unallocated space.
The new helper function called is_stmt_prepare_or_first_stmt_execute
is added to the Query_arena class.
The find_field_in_view function now uses
is_stmt_prepare_or_first_stmt_execute() to check whether
newly created view items should be freed at the end of the query execution.
The Item_cond::compile function now saves changes it makes to item tree.
The bug 38816 changed the lock that protects THD::query from
LOCK_thread_count to LOCK_thd_data, but didn't update the associated
InnoDB functions.
1. The innobase_mysql_prepare_print_arbitrary_thd and the
innobase_mysql_end_print_arbitrary_thd InnoDB functions have been
removed, since now we have a per-thread mutex: now we don't need to wrap
several inter-thread access tries to THD::query with a single global
LOCK_thread_count lock, so we can simplify the code.
2. The innobase_mysql_print_thd function has been modified to lock
LOCK_thd_data in direct way.
BUG#46000 - using index called GEN_CLUST_INDEX crashes server
Detailed revision comments:
r6180 | jyang | 2009-11-17 10:54:57 +0200 (Tue, 17 Nov 2009) | 7 lines
branches/5.0: Merge/Port fix for bug #46000 from branches/5.1
-r5895 to branches/5.0. Disallow creating index with the
name of "GEN_CLUST_INDEX" which is reserved for the default
system primary index. Minor adjusts on table name screening
format for added tests.
BUG#47777 - innodb dies with spatial pk: Failing assertion: buf <= original_buf + buf_len
Detailed revision comments:
r6178 | jyang | 2009-11-17 08:52:11 +0200 (Tue, 17 Nov 2009) | 6 lines
branches/5.0: Merge fix for bug #47777 from branches/5.1 -r6045
to bracnches/5.0. Treat the Geometry data same as Binary BLOB
in ha_innobase::store_key_val_for_row(), since the Geometry
data is stored as Binary BLOB in Innodb.
Fixed 2 errors in comp_err executable :
1. Wrong (off by 1) length passed to my_checksum()
2. strmov() was used on overlapping strings. This is
not legal according to the docs in stpcpy(). Used
the overlap safe memmove() instead.
WHERE conditions
check_group_min_max() checks if the loose index scan
optimization is applicable for a given WHERE condition, that is
if the MIN/MAX attribute participates only in range predicates
comparing the corresponding field with constants.
The problem was that it considered the whole predicate suitable
for the loose index scan optimization as soon as it encountered
a constant as a predicate argument. This is obviously wrong for
cases when a constant is the first argument of a predicate
which does not satisfy the above condition.
Fixed check_group_min_max() so that all arguments of the input
predicate are considered to decide if it passes the test, even
though a constant has already been encountered.
Until-pos guarding did not distiguish the master originated events from ones that the slave
can introduce to the relay log e.g Rotate to the next relay log at slave restarting.
The local Rotate's coordinate are incomparable with the Until-master-pos.
That led to the unexpectable stop this bug describes.
Fixed with to avoid Until-master-pos comparison for a local slave's event.
Notice that if --replicate-same-server is true such event is treated as coming from
the master side.
memory
The server was doing a bad class typecast causing setting of
wrong value for the maximum number of items in an internal
structure used in equality propagation.
Fixed by not doing the wrong typecast and asserting the type
of the Item where it should be done.
values
We should re-set the access method functions when changing the access
method when switching to another index to avoid sorting.
Fixed by doing a little re-engineering : encapsulating all the function
assignment into a special function and calling it when flipping the
indexes.
only const tables
The problem was caused by two shortcuts in the optimizer that
are inapplicable in the ROLLUP case.
Normally in a case when only const tables are involved in a
query, DISTINCT clause can be safely optimized away since there
may be only one row produced by the join. Similarly, we don't
need to create a temporary table to resolve DISTINCT/GROUP
BY/ORDER BY. Both of these are inapplicable when the WITH
ROLLUP modifier is present.
Fixed by disabling the said optimizations for the WITH ROLLUP
case.
Just change mysql_foo to mysql_cv_foo for one cache-id variable name. There
was only one bad variable name, present in 5.0 and 5.1, but not in the -pe
branch.
