In case of ROW item each compared pair does not
check if argumet collations can be aggregated and
thus appropiriate item conversion does not happen.
The fix is to add the check and convertion for ROW
pairs.
Assertion `0' failed
If ROW item is a part of an expression that also has
aggregate function calls (COUNT/SUM/AVG...), a
"splitting" with an Item::split_sum_func2 function
is applied to that ROW item.
Current implementation of Item::split_sum_func2
replaces this Item_row with a newly created
Item_aggregate_ref reference to it.
Then the row cache tries to work with the
Item_aggregate_ref object as with the Item_row object:
row cache calls row-emulation methods such as cols and
element_index. Item_aggregate_ref (like it's parent
Item_ref) inherits dummy implementations of those
methods from the hierarchy root Item, and call to
them leads to failed assertions and wrong data
output.
Row-emulation virtual functions (cols, element_index, addr,
check_cols, null_inside and bring_value) of Item_ref have
been overloaded to forward calls to an underlying item
reference.
are used as arguments of the IN predicate.
Added a function to check compatibility of row expressions. Made sure that this
function to be called for Item_func_in objects by fix_length_and_dec().
conditions.
When allocating memory for KEY_FIELD/SARGABLE_PARAM structures the
function update_ref_and_keys did not take into account the fact that
a single row equality could be replaced by several simple equalities.
Fixed by adjusting the counter cond_count accordingly for each subquery
when performing substitution of a row equality for simple equalities.
account by the optimizer.
Now all row equalities are converted into conjunctions of
equalities between row elements. They are taken into account
by the optimizer together with the original regular equality
predicates.
Added more DBUG statements
Ensure that we are comparing end space with BINARY strings
Use 'any_db' instead of '' to mean any database. (For HANDLER command)
Only strip ' ' when comparing CHAR, not other space-like characters (like \t)
