Created tests for "delete" based on update_use_source.test
For the update_use_source.test tests, data recovery in the table has been changed
from a rollback transaction to a complete delete and re-insert of the data with
optimize table. Cases are now being checked on three engines.
Added tests for update/delete with LooseScan and DuplicateWeedout optimization strategies
Added tests for engine MEMORY on delete and update
Added tests for multi-update with JSON_TABLE
Added tests for multi-update and multi-delete for engine Connect
This patch allows to use semi-join optimization at the top level of
single-table update and delete statements.
The problem of supporting such optimization became easy to resolve after
processing a single-table update/delete statement started using JOIN
structure. This allowed to use JOIN::prepare() not only for multi-table
updates/deletes but for single-table ones as well. This was done in the
patch for mdev-28883:
Re-design the upper level of handling UPDATE and DELETE statements.
Note that JOIN::prepare() detects all subqueries that can be considered
as candidates for semi-join optimization. The code added by this patch
looks for such candidates at the top level and if such candidates are found
in the processed single-table update/delete the statement is handled in
the same way as a multi-table update/delete.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
