Added a case for bug #4976 when one of the inner tables is empty.
select.result, join.result:
Reversed the previous change of the erronious fix for bug #4976.
sql_select.cc:
The previous fix for bug 4976 was reversed as it
erroniously converted an outer join into an innner join
when on_expression does not refer to outer tables.
This is not valid if inner tables return an empty set.
Setting dependency on outer tables was added for the above cases.
To fix the crash in the test case of bug #4976
a guard was added that blocks running the crashing code for
nested outer joins.
from the select list and TEXT field
make setup_copy_fields to insert Item_copy_string for blobs in
the beginning of the copy_funcs (push_back instead of push_front)
the thing is that Item_copy_string::copy for function can call
Item_copy_string::val_int for blob via Item_ref.
But if Item_copy_string::copy for blob isn't called before,
it's value will be wrong.
So all the Item_copy_string::copy for blobs should be called before
Item_copy_string::copy for functions.
do not use '' as user in tests, because it picks the Unix login (which gives unexpected results if it is 'root')
(such behaviour is a feature of mysql_real_connect(), see the manual).
Added test case for bug #4767.
item_sum.cc:
Added a correct setting of the maybe_null flag for a copy of
an Item_sum object where the argument was a field of an inner table
in an outer join read from a temporary table.
It's part of the fix for bug #4767.
sql_select.cc:
Made change_refs_to_tmp_fields work correctly
for test case of bug #4767 where Item_sum::get_tmp_table_item
failed to build a correct copy of an Item_sum object referring
to a field in a temporary table.
It looks like a hack yet.
Bug#4417: SHOW CREATE TABLE and SHOW COLUMNS now return consistent results when "SET NAMES BINARY", i.e. everything is sent in UTF8: column names, enum values, default values.
Fixed bug #4976.
join_nested.result, join_nested.test:
Added a test case for bug #4976.
sql_select.cc:
Applied conversion from an outer join to an inner join
when the on expression does not depend on the outer table.
It fixed bug #4976.
Instead of trying to open time zone tables during calculation of CONVERT_TZ() function
or setting of @@time_zone variable we should open and lock them with the rest of
statement's table (so we should add them to global table list) and after that use such
pre-opened tables for loading info about time zones.
