If a stored function or a trigger was killed it had aborted but no error
was thrown. This allows the caller statement to continue without a notice.
This may lead to a wrong data being inserted/updated to/deleted as in such
cases the correct result of a stored function isn't guaranteed. In the case
of triggers it allows the caller statement to ignore kill signal and to
waste time because of re-evaluation of triggers that always will fail
because thd->killed flag is still on.
Now the Item_func_sp::execute() and the sp_head::execute_trigger() functions
check whether a function or a trigger were killed during execution and
throws an appropriate error if so.
Now the fill_record() function stops filling record if an error was reported
through thd->net.report_error.
being used without being def
Inside method Item_func_unsigned::val_int, the variable value
can be returned without being initialized when the CAST argument
is of type DECIMAL and has a NULL value. This gives a run-time
error when building debug binaries using Visual C++ 2005.
Solution: Initialize value to 0
- Adding variable m_cached_result_type to keep the variable type consistent
during the execution of a statement.
- Before each result set is returned to the client the description of each
column is sent as meta data.
Previously the result type for a column could change if the hash variable
entry changed between statements. This caused the result set of the query
to alternate column types in certain cases which is not supported by MySQL
client-server protocol. Example:
Previously this sequence:
SET @a:=1;
SELECT @a:="text", @a;
would return "text", "text";
After the change the SELECT returns "text", 0
The reson for this is that previously the result set from 'SELECT @a;'
would always be of the type STRING, whereas now the type of the variable
is taken from the last SET statement. However, 'SELECT @a:="text"' will
return type of STRING since the right side of the assignment is used.
- Since isinf() portability across various platforms and
compilers is a complicated question, we should not use
it directly. Instead, the my_isinf() macro should be used,
which is defined as an alias to the system-defined isinf()
if it is safe to use, or a workaround implementation otherwise
The following type conversions was done:
- Changed byte to uchar
- Changed gptr to uchar*
- Change my_string to char *
- Change my_size_t to size_t
- Change size_s to size_t
Removed declaration of byte, gptr, my_string, my_size_t and size_s.
Following function parameter changes was done:
- All string functions in mysys/strings was changed to use size_t
instead of uint for string lengths.
- All read()/write() functions changed to use size_t (including vio).
- All protocoll functions changed to use size_t instead of uint
- Functions that used a pointer to a string length was changed to use size_t*
- Changed malloc(), free() and related functions from using gptr to use void *
as this requires fewer casts in the code and is more in line with how the
standard functions work.
- Added extra length argument to dirname_part() to return the length of the
created string.
- Changed (at least) following functions to take uchar* as argument:
- db_dump()
- my_net_write()
- net_write_command()
- net_store_data()
- DBUG_DUMP()
- decimal2bin() & bin2decimal()
- Changed my_compress() and my_uncompress() to use size_t. Changed one
argument to my_uncompress() from a pointer to a value as we only return
one value (makes function easier to use).
- Changed type of 'pack_data' argument to packfrm() to avoid casts.
- Changed in readfrm() and writefrom(), ha_discover and handler::discover()
the type for argument 'frmdata' to uchar** to avoid casts.
- Changed most Field functions to use uchar* instead of char* (reduced a lot of
casts).
- Changed field->val_xxx(xxx, new_ptr) to take const pointers.
Other changes:
- Removed a lot of not needed casts
- Added a few new cast required by other changes
- Added some cast to my_multi_malloc() arguments for safety (as string lengths
needs to be uint, not size_t).
- Fixed all calls to hash-get-key functions to use size_t*. (Needed to be done
explicitely as this conflict was often hided by casting the function to
hash_get_key).
- Changed some buffers to memory regions to uchar* to avoid casts.
- Changed some string lengths from uint to size_t.
- Changed field->ptr to be uchar* instead of char*. This allowed us to
get rid of a lot of casts.
- Some changes from true -> TRUE, false -> FALSE, unsigned char -> uchar
- Include zlib.h in some files as we needed declaration of crc32()
- Changed MY_FILE_ERROR to be (size_t) -1.
- Changed many variables to hold the result of my_read() / my_write() to be
size_t. This was needed to properly detect errors (which are
returned as (size_t) -1).
- Removed some very old VMS code
- Changed packfrm()/unpackfrm() to not be depending on uint size
(portability fix)
- Removed windows specific code to restore cursor position as this
causes slowdown on windows and we should not mix read() and pread()
calls anyway as this is not thread safe. Updated function comment to
reflect this. Changed function that depended on original behavior of
my_pwrite() to itself restore the cursor position (one such case).
- Added some missing checking of return value of malloc().
- Changed definition of MOD_PAD_CHAR_TO_FULL_LENGTH to avoid 'long' overflow.
- Changed type of table_def::m_size from my_size_t to ulong to reflect that
m_size is the number of elements in the array, not a string/memory
length.
- Moved THD::max_row_length() to table.cc (as it's not depending on THD).
Inlined max_row_length_blob() into this function.
- More function comments
- Fixed some compiler warnings when compiled without partitions.
- Removed setting of LEX_STRING() arguments in declaration (portability fix).
- Some trivial indentation/variable name changes.
- Some trivial code simplifications:
- Replaced some calls to alloc_root + memcpy to use
strmake_root()/strdup_root().
- Changed some calls from memdup() to strmake() (Safety fix)
- Simpler loops in client-simple.c
Since isinf() portability across various platforms and compilers is a complicated question, we should not use it directly. Instead, the my_isinf() macro should be used, which is defined as an alias to the system-defined isinf() if it is safe to use, or a workaround implementation otherwise.
The LEAST/GREATEST functions compared DATE/DATETIME values as
strings which in some cases could lead to a wrong result.
A new member function called cmp_datetimes() is added to the
Item_func_min_max class. It compares arguments in DATETIME context
and returns index of the least/greatest argument.
The Item_func_min_max::fix_length_and_dec() function now detects when
arguments should be compared in DATETIME context and sets the newly
added flag compare_as_dates. It indicates that the cmp_datetimes() function
should be called to get a correct result.
Item_func_min_max::val_xxx() methods are corrected to call the
cmp_datetimes() function when needed.
Objects of the Item_splocal class now stores and reports correct original
field type.
The generic string to int conversion was used by the Item_func_signed and
the Item_func_unsigned classes to convert DATE/DATETIME values to the
SIGNED/UNSIGNED type. But this conversion produces wrong results for such
values.
Now if the item which result has to be converted can return its result as
longlong then the item->val_int() method is used to allow the item to carry
out the conversion itself and return the correct result.
This condition is checked in the Item_func_signed::val_int() and the
Item_func_unsigned::val_int() functions.
