In this issue we are using derived_with_keys optimization and we are using these keys to do a hash join which is incorrect.
We cannot create keys for dervied tables whose keyparts have types are of BLOB or TEXT type. TEXT or BLOB columns can only be
indexed over a specified length.
MDEV-16512 Server crashes in find_field_in_table_ref on 2nd
execution of SP referring to non-existing field
Problem was in the natural join code that it changed TABLE_LIST and
Item_fields but didn't restore changed things if things goes wrong
and was not able to re-execute after failure.
Some of the problems could have been avoided if we would have run
fix_fields before doing natural join transformations.
Fixed by marking functions complete AFTER they had executed, instead at
start.
I had also to change some tests that checked if Item_fields are usable.
This doesn't fix all known problems, but at least avoids some crashes.
What should be done in the near future is to mark the statement in the SP
as 'not re-executable' and force a reparse of it on next execution.
Reviewer: Sergei Petrunia <psergey@askmonty.org>
materialization scan over materialization lookup
For non-mergeable semi-joins we don't store the estimates of the IN subquery in table->file->stats.records.
In the function TABLE_LIST::fetch_number_of_rows, we store the number of rows in the tables
(estimates in case of derived table/views).
Currently we don't store the estimates for non-mergeable semi-joins, which leads to a problem of selecting
materialization scan over materialization lookup.
Fixed this by storing these estimated appropriately
instrument table->record[0], table->record[1] and share->default_values.
One should not access record image beyond share->reclength, even
if table->record[0] has some unused space after it (functions that
work with records, might get a copy of the record as an argument,
and that copy - not being record[0] - might not have this buffer space
at the end). See b80fa4000d and 444587d8a3
TRASH was mapped to TRASH_FREE and was supposed to be used for memory
that should not be accessed anymore, while TRASH_ALLOC() is to be
used for uninitialized but to-be-used memory.
But sometimes TRASH() was used in the latter sense.
Remove TRASH() macro, always use explicit TRASH_ALLOC() or TRASH_FREE().
If translation table present when we materialize the derived table then
change it to point to the materialized table.
Added debug info to see really what happens with what derived.
IS DROPPED
ANALYSIS:
=========
It is advised not to tamper with the system tables.
When primary key is dropped from a system table, certain
operations on the table which tries to access the table key
information may lead to server exit.
FIX:
====
An appropriate error is now reported in such a case.
For BIT field null_bit is not set to 0 even for a field defined as NOT NULL.
So now in the function TABLE::create_key_part_by_field, if the bit field is not nullable
then the null_bit is explicitly set to 0
followup for 97c2a7354b - don't use thd->is_error(),
the error could've been set before TABLE_LIST::cleanup_items.
Use the error handler to count errors.
This fixes rpl.rpl_row_binlog_max_cache_size - it was failing when
ER_STMT_CACHE_FULL happened duing multi-table update. Because
multi_update::abort_result_set() calls do_updates() to update
as much as possible, so one cannot rely on thd->is_error() after that.
it used current_thd->alloc() and allocated on the thd's execution arena,
not on table->expr_arena.
Remove THD::arena_for_cached_items that is temporarily set in
update_virtual_fields(), and replaces THD arena in get_datetime_value().
Instead set THD arena to table->expr_arena for the whole duration
of update_virtual_fields()
The patch fixes the problem with loading information from system tables
(e.g. event and help related tables) when PAD_CHAR_TO_FULL_LENGTH is enabled,
as well as includes some additional minor improvements:
- refactoring in get_field() to return an error rather than success
if strmake_root() failed
- removing of duplicate code in similar functions:
char *get_field(MEM_ROOT *mem, Field *field)
bool get_field(MEM_ROOT *mem, Field *field, String *res)
__MEMMOVE_SSSE3_BACK FROM STRING::COPY
Issue:
-----
While using row comparators, the store_value functions call
val_xxx functions in the prepare phase. This can cause
valgrind issues.
SOLUTION:
---------
Setting up of the comparators should be done by
alloc_comparators in the prepare phase. Also, make sure
store_value will be called only during execute phase.
This is a backport of the fix for Bug#17755540.
Problem: Not all permanent Item_direct_view_ref was in permanent list of used items of the view.
Solution: Detect creating permenent view/derived table reference and put them in the permanent list at once.
This is MDEV-7601, including it's sub tasks MDEV-7594, MDEV-7555, MDEV-7590, MDEV-7581, MDEV-7589
The problem was that select_lex->non_agg_fields was not properly reset for re-execution and this caused an overwrite of a random memory position.
The fix was move non_agg_fields from select_lext to JOIN, which is properly reset.
Taking into account implicit dependence of constant view field from nullable table of left join added.
Fixed finding real table to check if it turned to NULL (materialized view & derived taken into account)
Removed incorrect uninitialization.
This bug manifests due to wrong computation and evaluation of
keyinfo->key_length. The issues were:
* Using table->file->max_key_length() as an absolute value that must not be
reached for a key, while it represents the maximum number of bytes
possible for a table key.
* Incorrectly computing the keyinfo->key_length size during
KEY_PART_INFO creation. The metadata information regarding the key
such the field length (for strings) was added twice.
Call mysql_derived_reinit() if we are reusing view.
This is needed as during a previous error condition the view may not have been reset
sql/sql_derived.cc:
More DBUG_PRINT
Always reset merged_for_insert (no reason to not do that)
sql/sql_derived.h:
Added prototype
sql/sql_insert.cc:
More DBUG_PRINT
Added DBUG_ASSERT
sql/sql_view.cc:
Call mysql_derived_reinit() if we are reusing view.
This is needed as during a previous error condition the view may not have been reset
sql/table.cc:
More DBUG_PRINT
