When resolving unqualified name references MySQL was not
checking what is the item type for the reference. Thus
e.g a string literal item that has by convention a name
equal to its string value will also work as a reference to
a SELECT list item or a table field.
Fixed by allowing only Item_ref or Item_field to referenced by
(unqualified) name.
Currently SQL_BIG_RESULT is checked only at compile time.
However, additional optimizations may take place after
this check that change the sort method from 'filesort'
to sorting via index. As a result the actual plan
executed is not the one specified by the SQL_BIG_RESULT
hint. Similarly, there is no such test when executing
EXPLAIN, resulting in incorrect output.
The patch corrects the problem by testing for
SQL_BIG_RESULT both during the explain and execution
phases.
optimizer does not honor IGNORE INDEX
- Allow an index to be used for sorting the table
instead of filesort only if it is not disabled by
IGNORE INDEX.
When making a place to store field values at the start of each group
the real item (not the reference) must be used when deciding which column
to copy.
length.
When temporary field created for DATE(LEFT(column,8)) expression, max_length
value is taken from Item_date_typecast, and it is getting it from underlaid
Item_func_left and it's max_length is 8 in given expression. And all this
results in stripping last 2 digits.
To Item_date_typecast class added its own fix_length_and_dec() function
that sets max_length value to 10, which is proper for DATE field.
Added a test case for bug #11414.
sql_select.cc:
Fixed bug #11414: crash on Windows with some simple
GROUP BY queries.
It happened to an allocation of an array containing
0 Copy_field elements in setup_copy_fields.
The bug had been already fixed in 5.0.
Added a test case for bug #11295.
item_buff.cc:
Fixed bug #11295.
This a correction for the patch of bug #11088 that takes into
account a possible NULL values of the BLOB column.
Added a test case for bug #11385.
group_by.test:
Added a test case for bug #11385.
field.h:
Fixed bug #11385.
The bug was due to not defined method decimals for the class
Field_datetime.
- Print warning that says display width is not supported for datatype TIMESTAMP, if user tries to create a TIMESTAMP column with display width.
- Use display width for TIMESTAMP only in type_timestamp test to make sure warning is displayed correctly.
Added a test case for bug #8614.
sql_select.cc:
Fixed bug #8614.
SELECT DISTINCT ... GROUP BY 'const' must be equivalent to
SELECT ... GROUP BY 'const'.
Fixed bug #11088: a crash for queries with GROUP BY a BLOB column
+ COUNT(DISTINCT...) due to an attempt to allocate a too large
buffer for the BLOB field.
Now the size of the buffer is limited by max_sort_length.
group_by.test, group_by.result:
Added a test case for bug #11088.
Ensure that references in HAVING, ORDER BY or GROUP BY are calculated after fields in SELECT.
This will ensure that any reference to these has a valid value.
Generalized the code for split_sum_func()
In Item_ref::Item_ref set maybe_null (and other fields fix_fields sets) to be the
same as in (*ref), because Item_ref::fix_fields() will not be called. Previously
maybe_null was 0 always and this produced a bogus state where
maybe_null==0 && is_null() == true
which broke evaluation for some upper-level Items, like AND and OR.
