MDEV-14957: JOIN::prepare gets unusable "conds" as argument
Do not touch merged derived (it is irreversible)
Fix first argument of in_optimizer for calls possible before fix_fields()
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.
The function mysql_derived_merge() erroneously did not mark newly formed
AND formulas in ON conditions with the flag abort_on_null. As a result
not_null_tables() calculated incorrectly for these conditions. This
could prevent conversion of embedded outer joins into inner joins.
Changed a test case from table_elim.test to preserve the former execution
plan.
The flag TABLE_LIST::fill_me must be reset to false at the prepare
phase for any materialized derived table used in the executed query.
Otherwise if the optimizer decides to generate a key for such a table
it is generated only for the first execution of the query.
Do not use merge_for_insert for commands which use SELECT because optimizer can't work with such tables.
Fixes which makes multi-delete working with normally merged views.
Main fix was to not cache derivied tables as they may be temporary tables that are deleted before the next query.
This was a bit tricky as Item_field::fix_fields depended on cached_tables to be set to resolve some columns.
mysql-test/r/sp-bugs.result:
Added test case
mysql-test/t/sp-bugs.test:
Added test case
sql/item.cc:
Fixed fix_outer_field to handle case where found field did not have in cached_table
Idea is that if cached_table is not avaliable, use from_field->table->pos_in_table_list instead
sql/records.cc:
Also accept INTERNAL_TMP_TABLE for memmap
sql/sql_base.cc:
More DBUG_PRINT
Fixed that setup_natural_join_row_types() is not run twice.
Original code modified context->first_name_resolution_table also for second executions.
This was wrong as this could give wrong results if some joins had been optimized away between calls.
sql/sql_derived.cc:
Mark derived tables as internal temporary tables (INTERNAL_TMP_TABLE), not as NON_TRANSACTIONAL_TMP_TABLE.
This is more correct as the tables are not visible by the end user.
sql/sql_insert.cc:
Reset pos_in_table_list before calling fix_fields.
One of the consequences of the change of not caching all generated tables in Item_ident is that
pos_in_table_list needs to be correct in calls to fix_fields.
sql/sql_lex.cc:
More DBUG_PRINT
sql/sql_parse.cc:
Don't cache derivied tables as they may be temporary tables that are deleted before the next query
sql/sql_select.cc:
Reset table_vector. This was required as some code checked the vector to see if temporary tables had already been created.
sql/table.cc:
Mark tables with field translations as cacheable (as these will not disapper between stmt executions.
THD::thd->activate_stmt_arena_if_needed() should be used to temporary activating statement arena instead of direct usage of THD::set_n_backup_active_arena() because possible such scenario:
1) func1 saves current arena and activates copy1 of statement arena
2) func2 saves copy1 of statement arena setup by func1 and activates copy2
3) some changes made for copy 2
4) func2 stores changed copy2 back to statenet arena and activates copy1
5) func1 store unchanged copy1 back to statemnt arena (rewrite changed copy 2 so changes become lost) and activates arena which was before.
Materialization forced in case if rand() used in view or derived table to avoud several calls of rand for gting value of a field.
Fixed set variable uncachable flag from - it shouldbe a side effect not a random value.
The bug caused a memory overwrite in the function update_ref_and_keys()
It happened due to a wrong value of SELECT_LEX::cond_count. This value
historically was calculated by the fix_fields method. Now the logic of
calling this method became too complicated and, as a result, this value
is calculated not always correctly.
The patch changes the way how and when the values of SELECT_LEX::cond_count
and of SELECT_LEX::between_count are calculated. The new code does it just at
the beginning of update_ref_and_keys().
Other fix of maybe_null problem and revert of revno: 3608 "MDEV-3873 & MDEV-3876 & MDEV-3912 : Wrong result (extra rows) with ALL subquery from a MERGE view."
mysql_derived_merge_for_insert() should not be called for views or derived tables which are not put (directly or via other views) in main SELECT_LEX "join list".
-Added test and extra code to ensure we don't leave keyread on for a handler table.
-Create on disk temporary files always with long data pointers if SQL_SMALL_RESULT is not used. This ensures that we can handle temporary files bigger than 4G.
mysql-test/include/default_mysqld.cnf:
Run test suite with smaller aria keybuffer size
mysql-test/suite/maria/maria3.result:
Run test suite with smaller aria keybuffer size
mysql-test/suite/sys_vars/r/aria_pagecache_buffer_size_basic.result:
Run test suite with smaller aria keybuffer size
sql/handler.cc:
Disable key read (extra safety if something went wrong)
sql/multi_range_read.cc:
Ensure we have don't leave keyread on for secondary_file
sql/opt_range.cc:
Simplify code with mark_columns_used_by_index_no_reset()
Ensure that read_keys_and_merge() disableds keyread if it enables it
sql/opt_subselect.cc:
Remove not anymore used argument for create_internal_tmp_table()
sql/sql_derived.cc:
Remove not anymore used argument for create_internal_tmp_table()
sql/sql_select.cc:
Use 'enable_keyread()' instead of calling HA_EXTRA_RESET. (Makes debugging easier)
Create on disk temporary files always with long data pointers if SQL_SMALL_RESULT is not used. This ensures that we can handle temporary files bigger than 4G.
Remove not anymore used argument for create_internal_tmp_table()
More DBUG
sql/sql_select.h:
Remove not anymore used argument for create_internal_tmp_table()
Do not call, directly or indirectly, SQL_SELECT::test_quick_select()
for derived materialized tables / views when optimizing joins referring
to these tables / views to get cost estimates of materialization.
The current code does not create B-tree indexes for materialized
derived tables / views. So now it's not possible to get any estimates
for ranges conditions over the results of the materialization.
The function mysql_derived_create() must take into account the fact
that array of the KEY structures specifying the keys over a derived
table / view may be moved after the optimization phase if the
derived table / view is materialized.
If the expression for a derived table of a query contained a LIMIT
clause the estimate of the number of rows in this derived table
returned by the EXPLAIN command could be badly off since the
optimizer ignored the limit number from the LIMIT clause when
getting the estimate.
The call of the method SELECT_LEX_UNIT->set_limit added in the code
of mysql_derived_optimize() will be needed also in maria-5.5 where
parameters in the LIMIT clause are supported.
sql/sql_insert.cc:
CREATE ... IF NOT EXISTS may do nothing, but
it is still not a failure. don't forget to my_ok it.
******
CREATE ... IF NOT EXISTS may do nothing, but
it is still not a failure. don't forget to my_ok it.
sql/sql_table.cc:
small cleanup
******
small cleanup
Also:
1. simplified the code of the function mysql_derived_merge_for_insert.
2. moved merge of views/dt for multi-update/delete to the prepare stage.
3. the list of the references to the candidates for semi-join now is
allocated in the statement memory.
