Also fixed a wrong result for a test case for mdev-7691
(the alternative one).
The test cases for all these bug have materialized semi-joins used
inside dependent sub-queries.
The patch actually reverts the change inroduced by Monty in 2003.
It looks like this change is not valid anymore after the implementation
of semi-joins.
Adjusted output from EXPLAIN for many other test cases.
be consistent and don't include the table name into the error message,
no other CREATE TABLE error does it.
(the crash happened, because thd->lex->query_tables was NULL)
Backport the fix olav.sandstaa@sun.com-20101102184747-qfuntqwj021imy9r:
"Fix for Bug#52660 Perf. regr. using ICP for MyISAM on range queries on an index containing TEXT"
(together with further fixes in that code) into MyISAM and Aria.
- In mi_rkey(), do correct handling of case where mi_yield_and_check_if_killed()
detects that the thread was killed (all other similar functions in MyISAM/Aria have
slightly different code and do not have this problem).
- Also fixed assignment in DBUG_ASSERT
- this is 2nd variant of the fix:
= make .result file smaller
= run KILLable statements in a separate connection, otherwise we could end up trying to
KILL the final "DROP TABLE" statement
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.
The function add_ref_to_table_cond missed updating the value of
join_tab->pre_idx_push_select_cond after having updated the value
of join_tab->select->pre_idx_push_select_cond.
The bug happened because in some cases the function JOIN::exec
did not save the value of TABLE::pre_idx_push_select_cond in
TABLE::select->pre_idx_push_select_cond for the sort table.
Noticed and fixed a bug in the function make_cond_remainder
that builds the remainder condition after extraction of an index
pushdown condition from the where condition. The code
erroneously assumed that the function make_cond_for_table left
the value of ICP_COND_USES_INDEX_ONLY in sub-condition markers.
Adjusted many result files from the regression test suite
after this fix .
The call of the virtual function cancel_pushed_idx_cond in the code of
the function test_if_skip_sort_order was misplaced when backporting the
fix for bug 58816.
This bug is a consequence of the fix in the function add_ref_to_table_cond
for LP bug 826935 that turned out to be not quite correct: it tried to AND
the same generated condition with two different other conditions.
This patch creates a copy of the generated condition if the condition needs
to be ANDed with two different items.
- add_ref_to_table_cond() should not just overwrite pre_idx_push_select_cond
with the contents tab->select_cond.
pre_idx_push_select_cond exists precisely for the reason that it may contain
a condition that is a strict superset of what is in tab->select_cond.
The fix is to inject generated equality into pre_idx_push_select_cond.
- Set the default
- Adjust the testcases so that 'new' tests are run with optimizations turned on.
- Pull out relevant tests from "irrelevant" tests and run them with optimizations on.
- Run range.test and innodb.test with both mrr=on and mrr=off
sql/multi_range_read.cc:
Added printing of error if something goes wrong in get_next()
(Not critical for this bug fix, but this was something that I noticed while testing and found missing)
storage/myisam/mi_rkey.c:
Fixed wrong error number in mi_yield_and_check_if_killed()
- In Maria/MyISAM: Release/re-acquire locks to give queries that wait on them a chance to make progress
- In Maria/MyISAM: Change from numeric constants to ICP_RES values.
- In Maria: Do check index condition in maria_rprev() (was lost in the merge/backport?)
- In Maria/MyISAM/XtraDB: Check if the query was killed, and return immediately if it was.
Added new storage engine error: HA_ERR_ABORTED_BY_USER, for handler to signal that it detected a kill of the query and aborted
Authors: Sergey Petrunia & Monty
include/my_base.h:
Added HA_ERR_ABORTED_BY_USER, for handler to signal that it detected a kill of the query and aborted
include/my_handler.h:
Added comment
mysql-test/r/myisam_icp.result:
Updated test
mysql-test/t/myisam_icp.test:
Drop used tables at start of test
Added test case that can help with manual testing of killing index condition pushdown query.
mysys/my_handler_errors.h:
Text for new storage engine error
sql/handler.cc:
If engine got HA_ERR_ABORTED_BY_USER, send kill message.
sql/multi_range_read.cc:
Return error code
storage/maria/ha_maria.cc:
Added ma_killed_in_mariadb() to detect kill.
Ensure that file->external_ref points to TABLE object.
storage/maria/ma_extra.c:
Dummy test-if-killed for standalone
storage/maria/ma_key.c:
If ma_check_index_cond() fails, set my_errno and info->cur_row.lastpos
storage/maria/ma_rkey.c:
Release/re-acquire locks to give queries that wait on them a chance to make progress
Check if the query was killed, and return immediately if it was
storage/maria/ma_rnext.c:
Check if the query was killed, and return immediately if it was
Added missing fast_ma_writeinfo(info)
storage/maria/ma_rnext_same.c:
Check if the query was killed, and return immediately if it was
Added missing fast_ma_writeinfo(info)
storage/maria/ma_rprev.c:
Check if the query was killed, and return immediately if it was
Added missing fast_ma_writeinfo(info) and ma_check_index_cond()
storage/maria/ma_search.c:
Give error message if we find a wrong key
storage/maria/ma_static.c:
Added pointer to test-if-killed function
storage/maria/maria_def.h:
New prototypes
storage/myisam/ha_myisam.cc:
Added mi_killed_in_mariadb()
Ensure that file->external_ref points to TABLE object.
storage/myisam/mi_extra.c:
Dummy test-if-killed for standalone
storage/myisam/mi_key.c:
If ma_check_index_cond() fails, set my_errno and info->lastpos
storage/myisam/mi_rkey.c:
Ensure that info->lastpos= HA_OFFSET_ERROR in case of error
Release/re-acquire locks to give queries that wait on them a chance to make progress
Check if the query was killed, and return immediately if it was
Reorder code to do less things in case of error.
Added missing fast_mi_writeinfo()
storage/myisam/mi_rnext.c:
Check if the query was killed, and return immediately if it was
Simplify old ICP code
Added missing fast_ma_writeinfo(info)
storage/myisam/mi_rnext_same.c:
Check if the query was killed, and return immediately if it was
Added missing fast_mi_writeinfo(info)
storage/myisam/mi_rprev.c:
Check if the query was killed, and return immediately if it was
Simplify error handling of ICP
Added missing fast_mi_writeinfo(info)
storage/myisam/mi_search.c:
Give error message if we find a wrong key
storage/myisam/mi_static.c:
Added pointer to test-if-killed function
storage/myisam/myisamdef.h:
New prototypes
storage/xtradb/handler/ha_innodb.cc:
Added DB_SEARCH_ABORTED_BY_USER and ha_innobase::is_thd_killed()
Check if the query was killed, and return immediately if it was
storage/xtradb/handler/ha_innodb.h:
Added prototype
storage/xtradb/include/db0err.h:
Added DB_SEARCH_ABORTED_BY_USER
storage/xtradb/include/row0mysql.h:
Added possible ICP errors
storage/xtradb/row/row0sel.c:
Use ICP errors instead of constants.
Detect if killed and return B_SEARCH_ABORTED_BY_USER
