fixed several defects in the greedy optimization:
1) The greedy optimizer calculated the 'compare-cost' (CPU-cost)
for iterating over the partial plan result at each level in
the query plan as 'record_count / (double) TIME_FOR_COMPARE'
This cost was only used locally for 'best' calculation at each
level, and *not* accumulated into the total cost for the query plan.
This fix added the 'CPU-cost' of processing 'current_record_count'
records at each level to 'current_read_time' *before* it is used as
'accumulated cost' argument to recursive
best_extension_by_limited_search() calls. This ensured that the
cost of a huge join-fanout early in the QEP was correctly
reflected in the cost of the final QEP.
To get identical cost for a 'best' optimized query and a
straight_join with the same join order, the same change was also
applied to optimize_straight_join() and get_partial_join_cost()
2) Furthermore to get equal cost for 'best' optimized query and a
straight_join the new code substrcated the same '0.001' in
optimize_straight_join() as it had been already done in
best_extension_by_limited_search()
3) When best_extension_by_limited_search() aggregated the 'best' plan a
plan was 'best' by the check :
'if ((search_depth == 1) || (current_read_time < join->best_read))'
The term '(search_depth == 1' incorrectly caused a new best plan to be
collected whenever the specified 'search_depth' was reached - even if
this partial query plan was more expensive than what we had already
found.
in EXPLAIN as select_type==MATERIALIZED.
Before, we had select_type==SUBQUERY and it was difficult to tell materialized
subqueries from uncorrelated scalar-context subqueries.
mysql-test/mysql-test-run.pl:
Rename MYSQLD -> MYSQLD_SIMPLE_CMD to avoid conflict with new MYSQLD variable from MySQL 5.1
mysql-test/r/innodb_file_format.result:
Remove old duplicated test
mysql-test/suite/pbxt/r/endspace.result:
Update test to last version
mysql-test/suite/pbxt/r/heap.result:
Removed heap test (not part of pbxt)
mysql-test/suite/pbxt/r/select_safe.result:
Updated results after error message change
mysql-test/suite/pbxt/r/view_grant.result:
Removed view test (not part of pbxt)
mysql-test/suite/pbxt/t/endspace.test:
Update test to last version
mysql-test/suite/pbxt/t/heap.test:
Removed heap test (not part of pbxt)
mysql-test/suite/pbxt/t/view_grant.test:
Removed view test (not part of pbxt)
mysql-test/t/innodb_file_format.test:
Remove old duplicated test
mysql-test/t/mysqld_option_err.test:
Use renamed variable
sql/my_decimal.h:
Fixed wrong define
storage/maria/ma_loghandler.c:
Fixed compiler warning
If the optimizer switch 'semijoin_with_cache' is set to 'off' then
join cache cannot be used to join inner tables of a semijoin.
Also fixed a bug in the function check_join_cache_usage() that led
to wrong output of the EXPLAIN commands for some test cases.
Analysis:
Equality propagation propagated the constant '7' into
args[0] of the Item_in_optimizer that stands for the
"< ANY" predicate. At the same the min/max subquery
rewrite swapped the order of the left and right operands
of the "<" predicate, but used Item_in_subselect::left_expr.
As a result, when the <ANY predicate is executed early in the
execution phase as a contant condition, instead of a constant
right (swapped) argument of the < predicate, there was a field
(t3.a). This field had no data, since the whole predicate is
considered constant, and it is evaluated before any tables are
read. Having junk in the field row buffer produced wrong result
Solution:
Fix create_swap to pick the correct Item_in_optimizer left
argument.
of the 5.3 code line after a merge with 5.2 on 2010-10-28
in order not to allow the cost to access a joined table to be equal
to 0 ever.
Expanded data sets for many test cases to get the same execution plans
as before.
ALL subquery should return TRUE if subquery rowa set is empty independently
of left part. The problem was that Item_func_(eq,ne,gt,ge,lt,le) do not
call execution of second argument if first is NULL no in this case subquery
will not be executed and when Item_func_not_all calls any_value() of the
subquery or aggregation function which report that there was rows. So for
NULL < ALL (SELECT...) result was FALSE instead of TRUE.
Fix is just swapping of arguments of Item_func_(eq,ne,gt,ge,lt,le) (with
changing the operation if it is needed) so that result will be the same
(for examole a < b is equal to b > a). This fix exploit the fact that
first argument will be executed in any case.
Analysis:
Constant table optimization of the outer query finds that
the right side of the equality is a constant that can
be used for an eq_ref access to fetch one row from t1,
and substitute t1 with a constant. Thus constant optimization
triggers evaluation of the subquery during the optimize
phase of the outer query.
The innermost subquery requires a plan with a temporary
table because with InnoDB tables the exact count of rows
is not known, and the empty tables cannot be optimzied
way. JOIN::exec for the innermost subquery substitutes
the subquery tables with a temporary table.
When EXPLAIN gets to print the tables in the innermost
subquery, EXPLAIN needs to print the name of each table
through the corresponding TABLE_LIST object. However,
the temporary table created during execution doesn't
have a corresponding TABLE_LIST, so we get a null
pointer exception.
Solution:
The solution is to forbid using expensive constant
expressions for eq_ref access for contant table
optimization. Notice that eq_ref with a subquery
providing the value is still possible during regular
execution.
This bug is a special case of lp:813447.
Analysis:
Constant optimization finds that the condition t2.a = 1
can be used to access the primary key of table 't2'. As
a result both outer table t1,t2 are considered as constant
when we reach the execution phase. At the same time, during
constant optimization, the IN predicate is not evaluated
because it is expensive.
When execution of the outer query reaches do_select(),
control flow enter the branch:
if (join->table_count == join->const_tables)
{ ... }
This branch checks only the WHERE and HAVING clauses,
but doesn't check the ON clauses of the query. Since the
IN predicate was not evaluated during optimization, it is
not evaluated at all, thus execution doesn't detect that
the ON clause is FALSE.
Solution:
Similar to the patch for bug lp:813447, exclude system
tables from constant substitution based on unique key
lookups if there is an expensive ON condition on the
inner table.
semijoin=on,firstmatch=on,loosescan=on
to
semijoin=off,firstmatch=off,loosescan=off
Adjust the testcases:
- Modify subselect*.test and join_cache.test so that all tests
use the same execution paths as before (i.e. optimizations that
are being tested are enabled)
- Let all other test files run with the new default settings (i.e.
with new optimizations disabled)
- Copy subquery testcases from these files into t/subselect_extra.test
which will run them with new optimizations enabled.
- The client gets a progress report message that triggers a callback function if requested with mysql_options(MYSQL_PROGRESS_CALLBACK, function)
- Added Progress field last to 'show processlist'
- Stage, Max_stage and Progress field added to information_schema.progresslist
- The 'mysql' client by defaults enables progress reports when the output is a tty.
- Added progress_report_time time variable to configure how often progress reports is sent to client
Added read only system variable 'in_transaction' which is 1 if we have executed a BEGIN statement.
client/client_priv.h:
Added OPT_REPORT_PROGRESS
client/mysql.cc:
Added option --progress-reports (on by default if not batch mode)
Progress reports is written to stdout for long running commands
include/Makefile.am:
Added mysql/service_progress_report.h
include/myisamchk.h:
Added variables to be able to do progress reporting in Aria and later in MyISAM
include/mysql.h:
Added new mysql_options() parameter: MYSQL_PROGRESS_CALLBACK
include/mysql.h.pp:
Added new mysql_options() parameter: MYSQL_PROGRESS_CALLBACK
include/mysql/plugin.h:
Added functions for reporting progress.
include/mysql/plugin_auth.h.pp:
Added functions for reporting progress.
include/mysql_com.h:
Added CLIENT_PROGRESS mysql_real_connect() flag.
include/sql_common.h:
Added callback function for reporting progress
mysql-test/r/old-mode.result:
Ensure that SHOW PROGRESSLIST doesn't have the Progress column in old mode.
mysql-test/suite/funcs_1/datadict/datadict_priv.inc:
Added new column
mysql-test/suite/funcs_1/datadict/processlist_priv.inc:
Test all new PROCESSLIST columns
mysql-test/suite/funcs_1/r/is_columns_is.result:
Updated results
mysql-test/suite/funcs_1/r/is_columns_is_embedded.result:
Updated results
mysql-test/suite/funcs_1/r/is_columns_mysql_embedded.result:
Updated results
mysql-test/suite/funcs_1/r/is_tables_is_embedded.result:
Updated results
mysql-test/suite/funcs_1/r/processlist_priv_no_prot.result:
Updated results
mysql-test/suite/funcs_1/r/processlist_priv_ps.result:
Updated results
mysql-test/suite/funcs_1/r/processlist_val_no_prot.result:
Updated results
mysql-test/suite/funcs_1/r/processlist_val_ps.result:
Updated results
mysql-test/suite/pbxt/r/pbxt_locking.result:
Updated results
mysql-test/suite/pbxt/r/skip_name_resolve.result:
Updated results
mysql-test/t/old-mode.test:
Ensure that SHOW PROGRESSLIST doesn't have the Progress column in old mode.
plugin/handler_socket/handlersocket/Makefile.am:
Added -lmysqlservices
scripts/mytop.sh:
Made 'State' field width dynamic.
Added 'Progress' to process list display.
sql-common/client.c:
Added handling of progress messages.
Removed check_license() function.
sql/mysql_priv.h:
Added opt_progress_report_time
sql/mysqld.cc:
Added progress_report_time time variable to configure how often progress reports is sent to client
sql/protocol.cc:
Added net_send_progress_packet()
sql/protocol.h:
New prototypes
sql/set_var.cc:
Added variables progress_report_time and in_transaction
sql/sql_acl.cc:
Safety fix: Made client_capabilities ulonglong
sql/sql_class.cc:
Added interface functions for progress reporting
sql/sql_class.h:
Added varibles in THD for progress reporting.
Added CF_REPORT_PROGRESS
sql/sql_load.cc:
Added progress reporting for LOAD DATA INFILE
sql/sql_parse.cc:
Added CF_REPORT_PROGRESS for top level commands for which it's safe to send progress reports to client
sql/sql_show.cc:
Added Progress field last to 'show processlist'
Stage, Max_stage and Progress field added to information_schema.progresslist
sql/sql_table.cc:
Added progress reporting for ALTER TABLE
Added THD as argument to copy_data_between_tables()
storage/maria/ha_maria.cc:
Added progress reporting for check table, repair table, analyze table
Fixed a bug in start_bulk_insert() that caused alter table to always run with all keys enabled.
storage/maria/ma_check.c:
Added progress reporting
Remember old state before starting repair. This removes some warnings from optimize_table if create-with-sort fails.
storage/maria/ma_check_standalone.h:
Added dummy reporting function for standalone Aria programs.
storage/maria/ma_sort.c:
Added progress reporting
storage/maria/maria_chk.c:
Updated version
storage/maria/maria_def.h:
Added new prototypes
tests/mysql_client_test.c:
Added test case for progress reporting
When looking for the execution plan of a derived table to be materialized
JOIN::optimize finds out that all joined tables of the derived table
contain not more than one row then the derived table should be maretialized
at the optimization stage.
Added a test case for the bug.
Adjusted results in other test cases.
