- move attempt to evaluate join->exec_const_cond() out of the "Extract constant part of each ON expression" loop
(it got there by mistake when merging).
Fixed reference to not initialized memory detected by valgrind
sql/sql_select.cc:
A bit better fix for tmp-table problem:
Use only dynamic_record format for group by and distinct.
storage/maria/ma_create.c:
DYNAMIC_RECORD format doesn't pack VARCHAR fields.
This change fixes a non-fatal uninitialized memory copy.
The reason for this is that BLOCK_RECORD format is not good when there is a lot of duplicated keys as it first writes the data (to get the row position) and
then writes the key (and thus checks for duplicates).
The code that added semi-join transformations missed checking
the state of the fixed flag for the items built with the
and_items function before calls of the fix_fields method.
This could lead to an abort failure when the first argument
of and_items() happened to be NULL.
introduced at the latest merge 5.1->5.2->5.3.
It is basically not needed since if SQL_SELECT::pre_idx_push_select_cond
is not NULL then SQL_SELECT::original_cond would point to the same condition
as SQL_SELECT::pre_idx_push_select_cond. Otherwise SQL_SELECT::original_cond
would be equal to SQL_SELECT::cond.
way of processing prepared statements:
- conversion subquery_predicate -> TABLE_LIST is once per-statement
- However, the code must take into account that materialized temptable
is dropped and re-created on each execution (the tricky part is that
at start of n-th EXECUTE we have TABLE_LIST object but not its TABLE object)
- IN-equality is injected into WHERE on every execution.
A lot of small fixes and new test cases.
client/mysqlbinlog.cc:
Cast removed
client/mysqltest.cc:
Added missing DBUG_RETURN
include/my_pthread.h:
set_timespec_time_nsec() now only takes one argument
mysql-test/t/date_formats.test:
Remove --disable_ps_protocl as now also ps supports microseconds
mysys/my_uuid.c:
Changed to use my_interval_timer() instead of my_getsystime()
mysys/waiting_threads.c:
Changed to use my_hrtime()
sql/field.h:
Added bool special_const_compare() for fields that may convert values before compare (like year)
sql/field_conv.cc:
Added test to get optimal copying of identical temporal values.
sql/item.cc:
Return that item_int is equal if it's positive, even if unsigned flag is different.
Fixed Item_cache_str::save_in_field() to have identical null check as other similar functions
Added proper NULL check to Item_cache_int::save_in_field()
sql/item_cmpfunc.cc:
Don't call convert_constant_item() if there is nothing that is worth converting.
Simplified test when years should be converted
sql/item_sum.cc:
Mark cache values in Item_sum_hybrid as not constants to ensure they are not replaced by other cache values in compare_datetime()
sql/item_timefunc.cc:
Changed sec_to_time() to take a my_decimal argument to ensure we don't loose any sub seconds.
Added Item_temporal_func::get_time() (This simplifies some things)
sql/mysql_priv.h:
Added Lazy_string_decimal()
sql/mysqld.cc:
Added my_decimal constants max_seconds_for_time_type, time_second_part_factor
sql/table.cc:
Changed expr_arena to be of type CONVENTIONAL_EXECUTION to ensure that we don't loose any items that are created by fix_fields()
sql/tztime.cc:
TIME_to_gmt_sec() now sets *in_dst_time_gap in case of errors
This is needed to be able to detect if timestamp is 0
storage/maria/lockman.c:
Changed from my_getsystime() to set_timespec_time_nsec()
storage/maria/ma_loghandler.c:
Changed from my_getsystime() to my_hrtime()
storage/maria/ma_recovery.c:
Changed from my_getsystime() to mmicrosecond_interval_timer()
storage/maria/unittest/trnman-t.c:
Changed from my_getsystime() to mmicrosecond_interval_timer()
storage/xtradb/handler/ha_innodb.cc:
Added support for new time,datetime and timestamp
unittest/mysys/thr_template.c:
my_getsystime() -> my_interval_timer()
unittest/mysys/waiting_threads-t.c:
my_getsystime() -> my_interval_timer()
mysql-test/r/subselect4.result:
Moved test case for LP BUG#718593 into the correct test file subselect_mat_cost_bugs.test.
mysql-test/t/subselect4.test:
Moved test case for LP BUG#718593 into the correct test file subselect_mat_cost_bugs.test.
Fields belonging to views in general cannot be substituted for
equal items, in particular for constants, because all references
to a view field refer to the same Item_field object while they
could be used in different OR parts of the where condition and
belong to different equivalence classes (to different Item_equals).
That's why substitution for equal items in any context is allowed
only in place of Item_direct_view_ref objects, but not in place of
Item_fields these objects refer to.
Due to some erroneous code in the patch for bug 717577 substitution
for view fields were allowed in some context.This could lead
to wrong results returned by queries using views.
The fix prohibits substitution of view fields for equal items
in any context.
The patch also changes slightly the compile method for the Item_func
class. Now if the analyze method returns NULL in his parameter the
compile method is not called for the arguments of the function
at all. A similar change was made for the Item_ref class.
sql/sql_select.cc:
- Threat all clustered indexes equal in test_if_skip_sort_order().
This is a temporary fix as the current code doesn't do proper cost analyizes for which index to use.
I will address this later as the change required is not trivial.
- Fixed a bug where select_limit was changed in the loop, which made different indexes see diferent values of select_limit
- Added a lot of code comments
- Updated get_best_ror_intersec() to prefer index scan on not clustered keys before clustered keys.
- Use HA_CLUSTERED_INDEX to define if one should use HA_MRR_INDEX_ONLY
- For test of using index or filesort to resolve ORDER BY, use HA_CLUSTERED_INDEX flag instead of primary_key_is_clustered()
- Use HA_TABLE_SCAN_ON_INDEX instead of primary_key_is_clustered() to decide if ALTER TABLE ... ORDER BY will have any effect.
sql/ha_partition.h:
Added comment with warning for code unsafe to use with multiple storage engines at the same time
sql/handler.h:
Added HA_CLUSTERED_INDEX.
Documented primary_key_is_clustered()
sql/opt_range.cc:
Added code comments
Updated get_best_ror_intersec() to ignore clustered keys.
Optimized away cpk_scan_used and one instance of current_thd (Simpler code)
Use HA_CLUSTERED_INDEX to define if one should use HA_MRR_INDEX_ONLY
sql/sql_select.cc:
Changed comment to #ifdef
For test of using index or filesort to resolve ORDER BY, use HA_CLUSTERED_INDEX flag instead of primary_key_is_clustered()
(Change is smaller than what it looks beause of indentation change)
sql/sql_table.cc:
Use HA_TABLE_SCAN_ON_INDEX instead of primary_key_is_clustered() to decide if ALTER TABLE ... ORDER BY will have any effect.
storage/innobase/handler/ha_innodb.h:
Added support for HA_CLUSTERED_INDEX
storage/innodb_plugin/handler/ha_innodb.cc:
Added support for HA_CLUSTERED_INDEX
storage/xtradb/handler/ha_innodb.cc:
Added support for HA_CLUSTERED_INDEX
Analysis:
The subquery is evaluated first during ref-optimization of the outer
query because the subquery is considered constant from the perspective
of the outer query. Thus an attempt is made to evaluate the MAX subquery
and use the new constant to drive an index nested loops join.
During this evaluation the inner-most subquery replaces the JOIN_TAB
with a new one that fetches the data from a temp table.
The function select_describe crashes at the lines:
TABLE_LIST *real_table= table->pos_in_table_list;
item_list.push_back(new Item_string(real_table->alias,
strlen(real_table->alias),
cs));
because 'table' is a temp table, and it has no corresponding table
reference. This 'real_table' is NULL, and real_table->alias results
in a crash.
Solution:
In the spirit of MWL#89 prevent the evaluation of expensive predicates
during optimization. This patch prevents the evaluation of expensive
predicates during ref optimization.
sql/item_subselect.h:
Remove unused class member. Not needed for the fix, but noticed now and removed.
sql/item_subselect.cc:
Cleanup. Comments added.
sql/item_subselect.h:
Cleanup.
sql/mysql_priv.h:
Comments added.
sql/opt_subselect.cc:
The function renamed and turned to method.
Comments added.
sql/opt_subselect.h:
The function turned to method of JOIN.
sql/sql_select.cc:
Comment added. The function turned to method.
sql/sql_select.h:
The function turned to method.
- In eliminate_item_equal(), we could end up in a situation where:
= The multiple equality has a constant C1 (and so it is the "head item")
= The join order was such that we've generated "sj_inner_table1=C1" equality,
and now are looking to generate "sj_inner_table2_=..." equality.
When looking for what should be the other member of equality, we run
Item *head_item= current_sjm? current_sjm_head: head;
which sees current_sjm!=NULL, and takes current_sjm_head (which is NULL because
the constant C1 is the head for all cases).
- Fixed in a trivial way: take current_sjm_head if we don't have constant.
Analysis:
The method st_select_lex::optimize_unflattened_subqueries()
incorrectly propagated to each subquery the complete
select_options flag set for the whole query. Among other
flags in select_options, this propagated incorrectly the
STRAIGHT_JOIN flag from the upper query to the subquery.
Solution:
During EXPLAIN set only the SELECT_DESCRIBE bit in the
select_options of the subquery.
The third parameter in the call of make_cond_for_table() that
built the pushed condition containing only outer references
was incorrect. This condition appeared for the first time in
the patch fixing bug 729039.
mysql-test/r/explain.result:
fixed results (new item)
mysql-test/r/subselect.result:
fixed results (new item)
mysql-test/r/subselect_no_mat.result:
fixed results (new item)
mysql-test/r/subselect_no_opts.result:
fixed results (new item)
mysql-test/r/subselect_no_semijoin.result:
Fixed results (new item)
mysql-test/suite/pbxt/r/subselect.result:
Fixed results (new item)
mysql-test/t/explain.test:
Fixed results (correct behaviour)
sql/item_cmpfunc.cc:
Pass through for max/min
sql/item_subselect.cc:
moving max/min
sql/item_subselect.h:
moving max/min
sql/mysql_priv.h:
new uncacheble flags added
sql/opt_subselect.cc:
maxmin moved.
sql/opt_subselect.h:
New function for maxmin.
sql/sql_class.h:
debug code
sql/sql_lex.cc:
Fixed flags.
Limit setting fixed.
sql/sql_lex.h:
2 new flags.
sql/sql_select.cc:
Prepare divided on 2 function to be able recollect some info after transformation.
sql/sql_select.h:
Prepare divided on 2 functions.
