* Fix the crash: IN-to-EXISTS rewrite causes an error (and so
JOIN::optimize() fails with an error, too), don't call
update_used_tables(). Terminate the query execution instead.
* Fix the cause of the error in the IN-to-EXISTS rewrite: don't do
the rewrite if doing it will cause an error of this kind:
This version of MariaDB doesn't yet support 'SUBQUERY in ROW in left
expression of IN/ALL/ANY'
* Fix another issue exposed by this testcase:
JOIN::setup_subquery_caches() may be invoked before any select has
saved its query plan, and will crash because none of the SELECTs
has called create_explain_query_if_not_exists() to create the Explain
Data Structure for this SELECT.
TODO: When merging this to 10.2, remove the poorly-placed call to
create_explain_query_if_not_exists made by fix for M_D_E_V-16153
Make differentiation between pullout for merge and pulout of outer field during exists2in transformation.
In last case the field was outer and so we can safely start from name resolution context of the SELECT where it was pulled.
Old behavior lead to inconsistence between list of tables and outer name resolution context (which skips one SELECT for merge purposes) which creates problem vor name resolution.
The implementation of the walk method for the class Item_in_subselect
was missing. As a result the method never traversed the left operand
of any IN subquery predicate.
Item_exists_subselect::exists2in_processor() that performs the
Exist-To-In transformation calls the walk method to collect info
on outer references. As the walk method did not traverse the
left operands of the IN subqueries the outer references there
were not taken into account and some subqueries that were actually
correlated were marked as uncorrelated. It could lead to an
attempt of the materialization of such a subquery.
Also added a cleanup for some test cases merged from 5.5.
The problem was that the view substitute its fields (on prepare) with reverting the change after execution. After prepare on optimization exists2in convertion substituted arguments of '=' with constsnt '1', but then one of the arguments of '=' was reverted to the view field reference.This lead to incorrect WHERE condition on the second execution.
To fix the problem we replace whole '=' with '1' permannently.
