forever, cannot be killed
mysql_rm_table_no_locks() does TDC_RT_REMOVE_ALL which waits while
share is closed. The table normally is open only as OPEN_STUB, this is
what parser does for CREATE TABLE. But for SELECT the table is opened
not as a stub. If it is the same table name we anyway have two
TABLE_LIST objects: stub and not stub. So for "not stub"
TDC_RT_REMOVE_ALL sees open count and decides to wait until it is
closed. And it hangs because that was opened in the same thread.
The fix disables subqueries in CHECK expression at parser
level. Thanks to Sergei Golubchik <serg@mariadb.org> for the patch.
INSERT IGNORE had a pecular undocumented case that when one row was
inserted, there was an error rather than a warning.
As LOAD DATA IGNORE, UPDATE IGNORE, INSERT IGNORE SELECT, and INSERT
IGNORE VALUES (single row, for foreign key violation) all behave the same
way with a warning lets keep the behaviour normalized.
In compatibility, previously a error was generated, now a warning is
generated.
This behaviour is now consistent with MySQL-8.0 too.
remove the hack where NO_DEFAULT_VALUE_FLAG was temporarily removed
from a field to initialize DEFAULT() functions in CHECK constraints
while disabling self-reference field checks.
Instead, initialize DEFAULT() functions in CHECK explicitly,
don't call check_field_expression_processor() for CHECK at all.
partially revert 76063c2a13. Item::clone() is not an all-purpose
Item copying machine, it was specifically created for pushdown
of predicates into derived tables and views and it does not
copy everything. In particular, it does not copy Item_func_regex.
Fix the bug differently by preserving the old constraint name.
But keep setting automatic_name=true to have it regenerated
for cases like ALTER TABLE ... ADD CONSTRAINT.
