ha_partition stores records in array of m_ordered_rec_buffer and uses
it for prio queue in ordered index scan. When the records are restored
from the array the blob buffers may be already freed or rewritten.
The solution is to take temporary ownership of cached blob buffers via
String::swap(). When the record is restored from m_ordered_rec_buffer
the ownership is returned to table fields.
Cleanups:
init_record_priority_queue(): removed needless !m_ordered_rec_buffer
check as there is same assertion few lines before.
dbug_print_row() for arbitrary row pointer
The issue here was the system variable max_sort_length was being applied
to decimals and it was truncating the value for decimals to the number
of bytes set by max_sort_length.
This was leading to a buffer overflow as the values were written
to the buffer without truncation and then we moved the offset to
the number of bytes(set by max_sort_length), that are needed for comparison.
The fix is to not apply max_sort_length for fixed size types like INT,
DECIMALS and only apply max_sort_length for CHAR, VARCHARS, TEXT and
BLOBS.
Make sure that the sort_buffer that is allocated has atleast space for MERGEBUFF2 keys.
The issue here was that the record length is quite high and sort buffer size is very small,
due to which we end up with zero number of keys in the sort buffer. The Sort_param::max_keys_per_buffer
was zero in such a case, due to which we were flushing empty sort_buffer to the disk.
The issue here is for a DEPENDENT subquery that has an aggregate function in the ORDER BY clause,
is wrapped inside an Item_aggregate_ref. For computation of ORDER BY we need to refer to the
temp table field corresponding to this item. But in the function make_sortorder, we were
explicitly casting Item_aggrgate_ref to Item_sum, which leads to us not getting the temp
table field corresponding to the item.
Make sure that the sort buffers can store atleast one sort key.
This is needed to make sure that all merge buffers are read else
with no sort keys some merge buffers are skipped because the code
makes a conclusion there is no data to be read.
cmake -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_BUILD_TYPE=Debug
Maintainer mode makes all warnings errors. This patch fix warnings. Mostly about
deprecated `register` keyword.
Too much warnings came from Mroonga and I gave up on it.
Modern compilers (such as GCC 8) emit warnings that the
'register' keyword is deprecated and not valid C++17.
Let us remove most use of the 'register' keyword.
Code in 'extra/' is not touched.
Handle string length as size_t, consistently (almost always:))
Change function prototypes to accept size_t, where in the past
ulong or uint were used. change local/member variables to size_t
when appropriate.
This fix excludes rocksdb, spider,spider, sphinx and connect for now.
Code in QUICK_RANGE_SELECT::init_ror_merged_scan() could theoretically
have caused crashes if this was ever called from an update or delete
This also found a bug in the vcol/range.result. file.
In the function make_sortkey a tmp buffer was defined and in the absence of
param->tmp_buffer, tmp buffer used the sort_keys buffer. sort_keys buffer
has a length defined in sort_field->length, while param->tmp_buffer is
stored in param->rec_length. Make sure to use the appropriate length
based on which buffer we are using otherwise we'll overflow.
Also added a type cast to size_t during the calculation of the sort keys
buffer size to avoid an oveflow if the buffer size exceeds 32 bits.
This fixes MDEV-7742 and MDEV-8305 (Allow user to specify if stored
procedures should be logged in the slow and general log)
New functionality:
- Added new variables log_slow_disable_statements and log_disable_statements
that can be used to disable logging of certain queries to slow and
general log. Currently supported options are 'admin', 'call', 'slave'
and 'sp'.
Defaults are as before. Only 'sp' (stored procedure statements) is
disabled for slow and general_log.
- Slow log to files now includes the following new information:
- When logging stored procedure statements the name of stored
procedure is logged.
- Number of created tmp_tables, tmp_disk_tables and the space used
by temporary tables.
- When logging 'call', the logged status now contains the sum of all
included statements. Before only 'time' was correct.
- Added filsort_priority_queue as an option for log_slow_filter (this
variable existed before, but was not exposed)
- Added support for BIT types in my_getopt()
Mapped some old variables to bitmaps (old variables can still be used)
- Variable 'log_queries_not_using_indexes' is mapped to
log_slow_filter='not_using_index'
- Variable 'log_slow_slave_statements' is mapped to
log_slow_disabled_statements='slave'
- Variable 'log_slow_admin_statements' is mapped to
log_slow_disabled_statements='admin'
- All the above variables are changed to session variables from global
variables
Other things:
- Simplified LOGGER::log_command. We don't need to check for super if
OPTION_LOG_OFF is set as this flag can only be set if one is a super
user.
- Removed some setting of enable_slow_log as it's guaranteed to be set by
mysql_parse()
- mysql_admin_table() now sets thd->enable_slow_log
- Added prepare_logs_for_admin_command() to reset thd->enable_slow_log if
needed.
- Added new functions to store, restore and add slow query status
- Added new functions to store and restore query start time
- Reorganized Sub_statement_state according to types
- Added code in dispatch_command() to ensure that
thd->reset_for_next_command() is always called for a query.
- Added thd->last_sql_command to simplify checking of what was the type
of the last command. Needed when logging to slow log as lex->sql_command
may have changed before slow logging is called.
- Moved QPLAN_TMP_... to where status for tmp tables are updated
- Added new THD variable, affected_rows, to be able to correctly log
number of affected rows to slow log.
- Added sql/mariadb.h file that should be included first by files in sql
directory, if sql_plugin.h is not used (sql_plugin.h adds SHOW variables
that must be done before my_global.h is included)
- Removed a lot of include my_global.h from include files
- Removed include's of some files that my_global.h automatically includes
- Removed duplicated include's of my_sys.h
- Replaced include my_config.h with my_global.h
These self references were previously used to avoid having to check the
IO_CACHE's type. However, a benchmark shows that on x86 5930k stock,
the type comparison is marginally faster than the double pointer dereference.
For 40 billion my_b_tell calls, the difference is .1 seconds in favor of performing the
type check. (Basically there is no measurable difference)
To prevent bugs from copying the structure using the equals(=) operator,
and having to do the bookkeeping manually, remove these "convenience"
variables.