If a derived table has SELECT DISTINCT, provide index statistics for it so that the join optimizer in the
upper select knows that ref access to the table will produce one row.
A sequence of <digits>e<mbhead><mbtail>, e.g.:
SELECT 123eXYzzz FROM t1;
was not scanned correctly (where XY is a multi-byte character).
The multi-byte head byte X was appended to 123e separately from
the multi-byte tail byte Y, so a pointer to "Yzzz" was passed
into scan_ident_start(), which failed on a bad multi-byte sequence.
After this change, scan_ident_start() gets a pointer to "XYzzz",
so it correctly sees the whole multi-byte character.
This also fixes:
MDEV-17299 Assertion `maybe_null' failed in make_sortkey
Note, during merge of the 10.1 version of MDEV-17299,
please use the 10.3 version of the code (i.e. null merge the 10.1 version).
When compiling CMAKE_BUILD_TYPE=Debug WITH_ASAN using clang-7 -O2
the following tests could fail due to insufficient stack size:
main.signal_demo3 sys_vars.max_sp_recursion_depth_func
If a splittable materialized derived table / view T is used in a inner nest
of an outer join with impossible ON condition then T is marked as a
constant table. Yet the execution plan to build T is still searched for
in spite of the fact that is not needed. So it should be set.
with UNION ALL after INTERSECT
EXPLAIN EXTENDED erroneously showed UNION instead of UNION ALL in
the warning if UNION ALL followed INTERSECT or EXCEPT operations.
The bug was in the function st_select_lex_unit::print() that printed
the text of the query used in the warning.
- CREATE TABLE ... SELECT drops constraints for columns that
are both in the create and select part.
- Fixed by copying the constraint in
Column_definiton::redefine_stage1_common()
- If one has both a default expression and check constraint for a
column, one can get the error "Expression for field `a` is refering
to uninitialized field `a`.
- Fixed by ignoring default expressions for current column when checking
for CHECK constraint
InnoDB does not allow creating multiple FULLTEXT INDEX
in ALGORITHM=INPLACE. This constraint was not being properly
enforced after MariaDB started to support ALGORITHM=INSTANT
and instant ADD COLUMN.
As a side effect of this bug, we again allow ALGORITHM=INPLACE
to rebuild a table when one FULLTEXT INDEX survives.
Also, we are returning a more accurate reason for refusing LOCK=NONE.
innobase_fulltext_exist(): Return the number of fulltext indexes.
ha_innobase::check_if_supported_inplace_alter(): If the table
needs to be rebuilt, refuse the operation if multiple fulltext
indexes would remain.
Alter statement changed the THD structure by setting the value to FIELD_CHECK_WARN
and then not resetting it back. This led ANALYZE to throw a warning which previously
it didn't.