The GROUP_CONCAT uses its own temporary table. When ROLLUP is present
it creates the second copy of Item_func_group_concat. This copy receives the
same list of arguments that original group_concat does. When the copy is
set up the result_fields of functions from the argument list are reset to the
temporary table of this copy.
As a result of this action data from functions flow directly to the ROLLUP copy
and the original group_concat functions shows wrong result.
Since queries with COUNT(DISTINCT ...) use temporary tables to store
the results the COUNT function they are also affected by this bug.
The idea of the fix is to copy content of the result_field for the function
under GROUP_CONCAT/COUNT from the first temporary table to the second one,
rather than setting result_field to point to the second temporary table.
To achieve this goal force_copy_fields flag is added to Item_func_group_concat
and Item_sum_count_distinct classes. This flag is initialized to 0 and set to 1
into the make_unique() member function of both classes.
To the TMP_TABLE_PARAM structure is modified to include the similar flag as
well.
The create_tmp_table() function passes that flag to create_tmp_field().
When the flag is set the create_tmp_field() function will set result_field
as a source field and will not reset that result field to newly created
field for Item_func_result_field and its descendants. Due to this there
will be created copy func to copy data from old result_field to newly
created field.
Bug #17257 ndb, update fails for inner joins if tables do not have Primary Key
change: the allocated area by setValue may not be around for later, store hidden key in special member variable instead
Bug #17158 load data infile of char values into table of char with no (PK) fails to load
Bug #17081 Doing "LOAD DATA INFILE" directly after delete can cause missing data
When setup_fields() function finds field named '*' it expands it to the list
of all table fields. It does so by checking that the first char of
field_name is '*', but it doesn't checks that the '* is the only char.
Due to this, when updating table with a field named like '*name', such field
is wrongly treated as '*' and expanded. This leads to making list of fields
to update being longer than list of the new values. Later, the fill_record()
function crashes by dereferencing null when there is left fields to update,
but no more values.
Added check in the setup_fields() function which ensures that the field
expanding will be done only when '*' is the only char in the field name.
fix for bug #15828 after review
doing val_str now before testing of null value secures the function for null values returned by dynamic functions - the fix before was incomplete andy covered constant null values
When InnoDB compares varchar field in ucs2 with given key using bin collation,
it calls my_strnncollsp_ucs2_bin() to perform comparison.
Because field length was lesser than length of key field should be padded
with trailing spaces in order to get correct result.
Because my_strnncollsp_ucs2_bin() was calling my_strnncollp_ucs2_bin(), which
doesn't pads field, wrong comparison result was returned. This results in
wrong result set.
my_strnncollsp_ucs2_bin() now compares fields like my_strnncollsp_ucs2 do,
but using binary collation.
field.cc:
BLOB variations have number-in-bytes limit,
unlike CHAR/VARCHAR which have number-of-characters limits.
A tinyblob column can store up to 255 bytes.
In the case of basic Latin letters (which use 1 byte per character)
we can store up to 255 characters in a tinyblob column.
When passing an utf8 tinyblob column as an argument into
a function (e.g. COALESCE) we need to reserve 3*255 bytes.
I.e. multiply length in bytes to mbcharlen for the character set.
Although in reality a tinyblob column can never be 3*255 bytes long,
we need to set max_length to multiply to make fix_length_and_dec()
of the function-caller (e.g. COALESCE) calculate the correct max_length
for the column being created.
ctype_utf8.result, ctype_utf8.test:
Adding test case.
for uca collation isalnum and strnncollsp don't agree on whether
0xC2A0 is a space (strnncollsp is right, isalnum is wrong).
they still don't, the bug was fixed by avoiding strnncollsp