ucs2 doesn't provide required by fulltext ctype array. Crash
happens because fulltext attempts to use unitialized ctype
array.
Fixed by converting ucs2 fields to compatible utf8 analogue.
DELETE query against memory table with btree index may remove
not all matching rows. This happens only when DELETE uses
index read method to find matching rows. E.g. for queries
like DELETE FROM t1 WHERE a=1.
Fixed by reverting fix for BUG9719 and applying proper solution.
SELECT statement itself returns empty.
As a result of this bug 'SELECT AGGREGATE_FUNCTION(fld) ... GROUP BY'
can return one row instead of an empty result set.
When GROUP BY only has fields of constant tables
(with a single row), the optimizer deletes the group_list.
After that we lose the information about whether we had an
GROUP BY statement. Though it's important
as SELECT min(x) from empty_table; and
SELECT min(x) from empty_table GROUP BY y; have to return
different results - the first query should return one row,
second - an empty result set.
So here we add the 'group_optimized_away' flag to remember this case
when GROUP BY exists in the query and is removed
by the optimizer, and check this flag in end_send_group()
This bug manifested itself for join queries with GROUP BY and HAVING clauses
whose SELECT lists contained DISTINCT. It occurred when the optimizer could
deduce that the result set would have not more than one row.
The bug could lead to wrong result sets for queries of this type because
HAVING conditions were erroneously ignored in some cases in the function
remove_duplicates.
The `SELECT 'r' INTO OUTFILE ... FIELDS ENCLOSED BY 'r' ' statement
encoded the 'r' string to a 4 byte string of value x'725c7272'
(sequence of 4 characters: r\rr).
The LOAD DATA statement decoded this string to a 1 byte string of
value x'0d' (ASCII Carriage Return character) instead of the original
'r' character.
The same error also happened with the FIELDS ENCLOSED BY clause
followed by special characters: 'n', 't', 'r', 'b', '0', 'Z' and 'N'.
NOTE 1: This is a result of the undocumented feature: the LOAD DATA INFILE
recognises 2-byte input sequences like \n, \t, \r and \Z in addition
to documented 2-byte sequences: \0 and \N. This feature should be
documented (here backspace character is a default ESCAPED BY character,
in the real-life example it may be any ESCAPED BY character).
NOTE 2, changed behaviour:
Now the `SELECT INTO OUTFILE' statement with the `FIELDS ENCLOSED BY'
clause followed by one of: 'n', 't', 'r', 'b', '0', 'Z' or 'N' characters
encodes this special character itself by doubling it ('r' --> 'rr'),
not by prepending it with an escape character.
Sometimes special 0 ENUM values was ALTERed to normal
empty string ENUM values.
Special 0 ENUM value has the same string representation
as normal ENUM value defined as '' (empty string).
The do_field_string function was used to convert
ENUM data at an ALTER TABLE request, but this
function doesn't care about numerical "indices" of
ENUM values, i.e. do_field_string doesn't distinguish
a special 0 value from an empty string value.
A new copy function called do_field_enum has been added to
copy special 0 ENUM values without conversion to an empty
string.
for a query over an empty table right after its creation.
The crash is the result of an attempt made by JOIN::optimize to evaluate
the WHERE condition when no records have been actually read.
The added test case can reproduce the crash only with InnoDB tables and
only with 5.0.x.
statement from a UNION query with ORDER BY an expression containing
RAND().
The crash happened because the global order by list in the union query
was not re-initialized for execution.
(Local order by lists were re-initialized though).
- Queries in the query cache are identified by the individual
characters in the query statement, the current database and
the current environment expressed as a set of system variable
flags.
- Since the set of environment flags didn't properly describe the
current environment unexpected results were returned from the
query cache.
- Query cache is now cleared when the variable ft_boolean_syntax is
updated.
- An identification flag for the variable default_week_format is
added to the query cache record.
Thanks to Martin Friebe who has supplied significant parts of this patch.
When checking for applicability of join cache
we must disable its usage only if there is no
temp table in use.
When a temp table is used we can use join
cache (and it will not make the result-set
unordered) to fill the temp table. The filesort()
operation is then applied to the data in the temp
table and hence is not affected by join cache
usage.
Fixed by narrowing the condition for disabling
join cache to exclude the case where temp table
is used.
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.
some rollup rows (rows with NULLs for grouping attributes) if GROUP BY
list contained constant expressions.
This happened because the results of constant expressions were not put
in the temporary table used for duplicate elimination. In fact a constant
item from the GROUP BY list of a ROLLUP query can be replaced for an
Item_null_result object when a rollup row is produced .
Now the JOIN::rollup_init function wraps any constant item referenced in
the GROYP BY list of a ROLLUP query into an Item_func object of a special
class that is never detected as constant item. This ensures creation of
fields for such constant items in temporary tables and guarantees right
results when the result of the rollup operation first has to be written
into a temporary table, e.g. in the cases when duplicate elimination is
required.
INSERT...ON DUPLICATE KEY UPDATE may cause error 1032:
"Can't find record in ..." if we are inserting into
InnoDB table unique index of partial key with
underlying UTF-8 string field.
This error occurs because INSERT...ON DUPLICATE uses a wrong
procedure to copy string fields of multi-byte character sets
for index search.
This bug occurs when error message length exceeds allowed limit: my_error()
function outputs "%s" sequences instead of long string arguments.
Formats like %-.64s are very common in errmsg.txt files, however my_error()
function simply ignores precision of those formats.
on a BLACKHOLE table
Using INSERT DELAYED on BLACKHOLE tables could lead to server
crash.
This happens because delayed thread wants to upgrade a lock,
but BLACKHOLE tables do not have locks at all.
This patch rejects attempts to use INSERT DELAYED on MERGE
tables.
