Analysis:
The queries in question use the [unique | index]_subquery execution methods.
These methods reuse the ref keys constructed by create_ref_for_key(). The
way create_ref_for_key() works is that it doesn't store in ref.key_copy[]
store_key elements that represent constants. In particular it doesn't store
the store_key for NULL constants.
The execution of [unique | index]_subquery calls
subselect_uniquesubquery_engine::copy_ref_key, which in addition to copy
the left IN argument into a index lookup key, is supposed to detect if
the left IN argument contains NULLs. Since the store_key for the NULL
constant is not copied into the key array, the null is not detected, and
execution erroneously proceeds as if it should look for a complete match.
Solution:
The solution (unlike MySQL) is to reuse already computed information about
NULL presence. Item_in_optimizer::val_int already finds out if the left IN
operand contains NULLs. The fix propagates this to the execution methods
subselect_[unique | index]subquery_engine::exec so it knows if there were
NULL values independent of the presence of keys.
In addition the patch siplifies copy_ref_key() and the logic that hanldes
the case of NULLs in the left IN operand.
Link view/derived table fields to a real table to check turning the table record to null row.
Item_direct_view_ref wrapper now checks if table is turned to null row.
Autointersections of an object were treated as nodes, so the wrong result.
per-file comments:
mysql-test/r/gis.result
Bug #1043845 st_distance() results are incorrect depending on variable order.
test result updated.
mysql-test/t/gis.test
Bug #1043845 st_distance() results are incorrect depending on variable order.
test case added.
sql/item.cc
small fix to make compilers happy.
sql/item_geofunc.cc
Bug #1043845 st_distance() results are incorrect depending on variable order.
Skip intersection points when calculate distance.
When we append data to the binlog file, we use fdatasync() to ensure
the data gets to disk so that crash recovery can work.
Unfortunately there seems to be a bug in ext3/ext4 on linux, so that
fdatasync() does not correctly sync all data when the size of a file
is increased. This causes crash recovery to not work correctly (it
loses transactions from the binlog).
As a work-around, use fsync() for the binlog, not fdatasync(). Since
we are increasing the file size, (correct) fdatasync() will most
likely not be faster than fsync() on any file system, and fsync()
does work correctly on ext3/ext4. This avoids the need to try to
detect if we are running on buggy ext3/ext4.
1. Field_newdate::get_date should refuse to return a date with zeros when
TIME_NO_ZERO_IN_DATE is set, not when TIME_FUZZY_DATE is unset
2. Item_func_to_days and Item_date_add_interval can only work with valid dates,
no zeros allowed.
fix Item_func_add_time::get_date() to generate valid dates.
Move the validity check inside get_date_from_daynr()
instead of relying on callers
(5 that had it, and 2 that did not, but should've)
The problem was that was_null and null_value variables was reset in each reexecution of IN subquery, but engine rerun only for non-constant subqueries.
Fixed checking constant in Item_equal sort.
Fix constant reporting in Item_subselect.
two tests still fail:
main.innodb_icp and main.range_vs_index_merge_innodb
call records_in_range() with both range ends being open
(which triggers an assert)
The bug could caused a crash when the server executed a query with
ORDER by and sort_buffer_size was set to a small enough number.
It happened because the small sort buffer did not allow to allocate
all merge buffers in it.
Made sure that the allocated sort buffer would be big enough
to contain all possible merge buffers.
Following reasons caused mismatches:
- different handling of invalid values;
- different CAST results with fractional seconds;
- microseconds support in MariaDB;
- different algorithm of comparing temporal values;
- differences in error and warning texts and codes;
- different approach to truncating datetime values to time;
- additional collations;
- different record order for queries without ORDER BY;
- MySQL bug#66034.
More details in MDEV-369 comments.
Following reasons caused mismatches:
- different handling of invalid values;
- different CAST results with fractional seconds;
- microseconds support in MariaDB;
- different algorithm of comparing temporal values;
- differences in error and warning texts and codes;
- different approach to truncating datetime values to time;
- additional collations;
- different record order for queries without ORDER BY;
- MySQL bug#66034.
More details in MDEV-369 comments.
- index_merge/intersection is unable to work on GIS indexes, because:
1. index scans have no Rowid-Ordered-Retrieval property
2. When one does an index-only read over a GIS index, they do not
get the index tuple, because index only contains bounding box of the geometry.
This is why key_copy() call crashed.
This patch fixes#1, which makes the problem go away. Theoretically, it would
be nice to check #2, too, but SE API semantics is not sufficiently precise to do it.
