Problem:
HASH indexes on VARCHAR columns with binary collations did not ignore trailing spaces from strings before comparisons. This could result in duplicate records being successfully inserted into a MEMORY table with unique key constraints.
As a direct consequence of the above, internal MEMORY tables used for GROUP BY calculation in testcases for bug #27643 contained duplicate rows which resulted in duplicate key errors when converting those temporary tables to MyISAM. Additionally, that error was incorrectly converted to the 'table is full' error.
Solution:
- ignore trailing spaces in VARCHAR fields with binary collations when calculating hashes.
- return a proper error from create_myisam_from_heap() when conversion fails.
mysqld crashed when a long-running explain query was killed from
another connection.
When the current thread caught a kill signal executing the function
best_extension_by_limited_search it just silently returned to
the calling function greedy_search without initializing elements of
the join->best_positions array.
However, the greedy_search function ignored thd->killed status
after a calls to the best_extension_by_limited_search function, and
after several calls the greedy_search function used an uninitialized
data from the join->best_positions[idx] to search position in the
join->best_ref array.
That search failed, and greedy_search tried to call swap_variables
function with NULL argument - that caused a crash.
ENUM fields internally store their values as integers and may use integer
values as indexes to their values. Invalid values are mapped to zero value.
When storing an empty string the ENUM field fails to find an appropriate value
and tries to convert the provided string to integer. The conversion also
fails and error is returned even if the thd->count_cuted_fields is set to
CHECK_FIELD_IGNORE. This makes the range optimizer wrongly decide that an
impossible range is present.
Now the Field_enum::store() returns error while storing an empty string only
if the thd->count_cuted_fields isn't set to CHECK_FIELD_IGNORE.
Problem: there is an ASSERT() in the Log_event::read_log_event() checking the integrity
of the event's data that may fail.
Fix: move the assert's condition to an explicit check.
The result of the CHECK OPTION condition evaluation over an
updated record and records of merged tables was arbitrary and
dependant on the order of records in the merged tables during
the execution of SELECT statement.
The CHECK OPTION expression was evaluated over expired record
buffers (with arbitrary data in the fields).
Rowids of tables used in the CHECK OPTION expression were
added to temporary table rows. The multi_update::do_updates()
method was modified to restore necessary record buffers
before evaluation of the CHECK OPTION condition.
Integer values with 10 digits may or may not fit into an int column
(e.g. 2147483647 vs 6147483647).
Thus when creating a temp table column for such an int we must
use bigint instead.
Fixed to use bigint.
Also subsituted a "magic number" with a named constant.
