Port the following patch from MySQL:
commit 1b2e8ea269c80cb93cc79d8be934c40b1c58e947
Author: Kailasnath Nagarkar <kailasnath.nagarkar@oracle.com>
Date: Fri Nov 30 16:43:13 2018 +0530
Bug #20939184: INNODB: UNLOCK ROW COULD NOT FIND A 2 MODE
LOCK ON THE RECORD
Issue:
------
Consdier tables t1 and t2 such that t1 has multiple rows
and join condition for t1 left join t2 results in only
single row from t2.
In this case, access to table t2 is const since there
is a single row that qualifies the join condition.
However, while executing the query, attempt is made to
unlock t2's row multiple times.
The current algorithm to fetch rows approximates to:
1) Retrieve the row for t1.
2) Retrieve the row for t2.
3) Apply the join conditions.
a) If condition evaluates to true:
Project the row to the result.
b) If condition evaluates to false:
i) If t2's qep_tab->not_null_complement is true,
unlock t2's row.
ii) Null-complement the row by calling
"evaluate_null_complemented_join_record()". In
this function qep_tab->not_null_complement is
set to false.
The t2's only one row, that qualifies join condition,
is unlocked in Step i) when t1's row is evaluated to
false.
When t1's next row is also evaluated to false, another
attempt is made to unlock t2's already unlocked row.
This results in following error being logged in error.log:
"[ERROR] InnoDB: Unlock row could not find a 3 mode lock on
the record. Current statement:
select * from t1 left join t2 ......"
Solution:
---------
When a table's access method is "const", set record unlock
method for this table to do no operation.
- IF EXISTS ends with a list of all not existing object, instead of a
separate note for every not existing object
- Produce a "Note" for all wrongly dropped objects
(like trying to do DROP SEQUENCE for a normal table)
- Do not write existing tables that could not be dropped to binlog
Other things:
MDEV-22820 Bogus "Unknown table" warnings produced upon attempt to drop
parent table referenced by FK
This was caused by an older version of this commit patch and later fixed
- multi_range_read_info_const now uses the new records_in_range interface
- Added handler::avg_io_cost()
- Don't calculate avg_io_cost() in get_sweep_read_cost if avg_io_cost is
not 1.0. In this case we trust the avg_io_cost() from the handler.
- Changed test_quick_select to use TIME_FOR_COMPARE instead of
TIME_FOR_COMPARE_IDX to align this with the rest of the code.
- Fixed bug when using test_if_cheaper_ordering where we didn't use
keyread if index was changed
- Fixed a bug where we didn't use index only read when using order-by-index
- Added keyread_time() to HEAP.
The default keyread_time() was optimized for blocks and not suitable for
HEAP. The effect was the HEAP prefered table scans over ranges for btree
indexes.
- Fixed get_sweep_read_cost() for HEAP tables
- Ensure that range and ref have same cost for simple ranges
Added a small cost (MULTI_RANGE_READ_SETUP_COST) to ranges to ensure
we favior ref for range for simple queries.
- Fixed that matching_candidates_in_table() uses same number of records
as the rest of the optimizer
- Added avg_io_cost() to JT_EQ_REF cost. This helps calculate the cost for
HEAP and temporary tables better. A few tests changed because of this.
- heap::read_time() and heap::keyread_time() adjusted to not add +1.
This was to ensure that handler::keyread_time() doesn't give
higher cost for heap tables than for normal tables. One effect of
this is that heap and derived tables stored in heap will prefer
key access as this is now regarded as cheap.
- Changed cost for index read in sql_select.cc to match
multi_range_read_info_const(). All index cost calculation is now
done trough one function.
- 'ref' will now use quick_cost for keys if it exists. This is done
so that for '=' ranges, 'ref' is prefered over 'range'.
- scan_time() now takes avg_io_costs() into account
- get_delayed_table_estimates() uses block_size and avg_io_cost()
- Removed default argument to test_if_order_by_key(); simplifies code
