Item_char_typecast::val_str_generic() uses Item::str_value as a buffer.
Item::val_str_ascii() also used Item::str_value as a buffer.
As a result, str_value tried to copy to itself.
Fixing val_str_ascii() to use a local buffer instead of str_value.
Updated tests: cases with bugs or which cannot be run
with the cursor-protocol were excluded with
"--disable_cursor_protocol"/"--enable_cursor_protocol"
Fix for v.10.5
RAND() and UUID() are treated differently with respect to subquery
materialization both should be marked as uncacheable, forcing materialization.
Altered Create_func_uuid(_short)::create_builder().
Added comment in header about UNCACHEABLE_RAND meaning also unmergeable.
This patch adds for "--ps-protocol" second execution
of queries "SELECT".
Also in this patch it is added ability to disable/enable
(--disable_ps2_protocol/--enable_ps2_protocol) second
execution for "--ps-prototocol" in testcases.
Tests with checking metadata or that cannot be run with
the view-protocol are excluded from --view-protocol.
For tests that do not allow the use of an additional connection,
the util connection is disabled with "--disable_service_connection".
Also cases with bugs for --view-protocol are disabled.
Detailed: changes:
1. Moving Field specific code into new methods on Field:
- Field *Field::create_tmp_field(...)
- virtual void init_for_tmp_table(...)
2. Removing virtual Item::create_tmp_field().
Adding instead a new virtual method Item::create_tmp_field_ex().
Note, a virtual create_tmp_field() still exists, but only for Item_sum.
This resembles 10.0 code structure. Perhaps create_tmp_field() should
be removed from Item_sum and Item_sum descendants should override
create_tmp_field_ex() directly. This can be done in a separate commit.
3. Adding helper classes Tmp_field_src and Tmp_field_param,
to make the API for Item::create_tmp_field_ex() smaller
and easier to extend in the future.
4. Decomposing the public function create_tmp_field() into
virtual implementations for Item and a number of its descendants:
- Item_basic_value
- Item_sp_variable
- Item_name_const
- Item_result_field
- Item_field
- Item_ref
- Item_type_holder
- Item_row
- Item_func_sp
- Item_func_user_var
- Item_sum
- Item_sum_field
- Item_proc
5. Adding DBUG_ASSERT-only virtual implementations for
Item types that should not appear in create_tmp_table_ex(),
for easier debugging:
- Item_nodeset_func
- Item_nodeset_to_const_comparator
- Item_null_result
- Item_copy
- Item_ident_for_show
- Item_user_var_as_out_param
6. Moving public function create_tmp_field_from_field()
as a method to Item_field.
7. Removing Item::set_result_field(). It's not needed any more.
8. Cleanup: Removing the enum value "EXPR_CACHE_ITEM",
as it's not used for a very long time.
