When using LEFT() function with a string that is without a charset,
the function crashes. This is because the function assumes that
the string has a charset, and tries to use it to calculate the
length of the string.
Two functions, UNHEX and WEIGHT_STRING, returned a string without
the charset being set to a not null value.
The fix is to set charset when calling val_str on these two functions.
Reviewed-by: Alexander Barkov <bar@mariadb.com>
Reviewed-by: Daniel Black <daniel@mariadb.org>
Making changes to wsrep_mysqld.h causes large parts of server code to
be recompiled. The reason is that wsrep_mysqld.h is included by
sql_class.h, even tough very little of wsrep_mysqld.h is needed in
sql_class.h. This commit introduces a new header file, wsrep_on.h,
which is meant to be included from sql_class.h, and contains only
macros and variable declarations used to determine whether wsrep is
enabled.
Also, header wsrep.h should only contain definitions that are also
used outside of sql/. Therefore, move WSREP_TO_ISOLATION* and
WSREP_SYNC_WAIT macros to wsrep_mysqld.h.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
Item::save_str_in_field() passes &Item::str_value as a parameter
to val_str().
Item_func::make_empty_result() also fills and returns str_value.
As a result, in the reported scenario in
Item_func::val_str_from_val_str_ascii()
both "str" and "res" pointed to Item::str_value,
which made the DBUG_ASSERT inside String::copy()
(preventing copying to itself) crash:
if ((null_value= str->copy(res->ptr(), res->length(),
&my_charset_latin1, collation.collation,
&errors)))
Fix:
- Adding a String* parameter to make_empty_result()
- Passing the val_str() parameter to make_empty_string().
We used to define a native unary function CRC32() that computes the CRC-32
of a string using the ISO 3309 polynomial that is being used by zlib
and many others.
Often, a CRC is computed in pieces. To faciliate this, we introduce a
2-ary variant of the function that inputs a previous CRC as the first
argument: CRC32('MariaDB')=CRC32(CRC32('Maria'),'DB').
InnoDB and MyRocks use a different polynomial, which was implemented
in SSE4.2 instructions that were introduced in the
Intel Nehalem microarchitecture. This is commonly called CRC-32C
(Castagnoli).
We introduce a native function that uses the Castagnoli polynomial:
CRC32C('MariaDB')=CRC32C(CRC32C('Maria'),'DB'). This allows
SELECT...INTO DUMPFILE to be used for the creation of files with
valid checksums, such as a logically empty InnoDB redo log file
ib_logfile0 corresponding to a particular log sequence number.
The reason for crash is that natural_sort_key(release_lock('a')) would
evaluate release_lock() twice, once in Item::is_null() and another time
in Item::val_str(). Second time it returns NULL, since lock was already
released.
Fixed to prevent double evaluation.
Leading zeros added a single byte overhead per numeric string,
even when they were. Sorting leading zeros offers only for little value
(except determinism in sort). I decided to drop it for now, we can be
like ICU, which drops leading zeros, in numeric sorting,
even with IDENTICAL collation strength.
Also, disabled virtual stored columns (thus also indexes), on Serg's request
Hopefully it is temporarily, and will be reenabled soon, when everyone is
as happy with key generation algorithm as I am.
- return error from natsort_encode_numeric_key, if it would need
to allocate memory. All needed memory was preallocated much earlier.
- Add test for sort order of leading zero vs numeric strings with suffix.
- Remove second optional parameter to natural_sort_key(), and all fraction
handling.
- Rename natsort_num2str() to natsort_encode_length() to show the intention
that it encodes string *lengths*, and not encode whitespaces and what not.
Handles lengths for which log10(len) >= 10, even if they do not happen for
MariaDB Strings (where length is limited by 32bit, and log10(len) is <= 9)
- Do not let natural sort key grow past max_packet_length.
- Split Item_func_natural_sort_key::val_str() further and add
natsort_encode_numeric_string(), which contains comment on how
whitespaces are handled.
- Simplify, and speedup to_natsort_key() in common case, by removing
handling of weird charsets utf16/32, that encode numbers in several bytes.
In rare cases utf16/32 is used, we'll convert to utf8 prior to
creating keys, and back to original charset afterwards.
The numbers should be compared as numbers, while the rest should be compared
as string.
Introduce natural_sort_key() function that transforms original string
so that the lexicographic order of such keys is suitable for
natural sort.
