mariadb

Commit Graph

Author	SHA1	Message	Date
Igor Babaev	b0395d8701	Fixed the bug mdev-12429 and its duplicates mdev-12145 and mdev-9886. 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.	9 years ago
Varun Gupta	adbe1c5fe9	MDEV-6486: Assertion `!table \|\| (!table->read_set \|\| bitmap_is_set(table->read_set, field_index))' failed with SELECT SQ, TEXT field The functon find_all_keys does call Item_subselect::walk, which calls walk() for the subquery The issue is that when a field is represented by Item_outer_ref(Item_direct_ref(Item_copy_string( ...))). Item_copy_string does have a pointer to an Item_field in Item_copy::item but does not implement Item::walk method, so we are not able to set the bitmap for that field. This is the reason why the assert fails. Fixed by adding the walk method to Item_copy class.	9 years ago
Varun Gupta	43903745e5	MDEV-11078: NULL NOT IN (non-empty subquery) should never return results Disabling the cond guards during the creation of Tricond Item for constant and NULL left expression items	9 years ago
Sergei Petrunia	268bb69bea	MDEV-7691: Assertion `outer_context \|\| !from_field \|\| from_field == not_found_field' ... The bug occurred when a subquery - has a reference to outside, to grand-parent query or further up - is converted to a semi-join (i.e. merged into its parent). Then the reference to outside had form Item_ref(Item_field(...)). - Conversion to semi-join would call item->fix_after_pullout() for the outside reference. - Item_ref::fix_after_pullout would call Item_field->fix_after_pullout - The Item_field would construct a new Name_resolution_context object This process ignored the fact that the Item_field does not belong to any of the subselects being flattened. The result was crash in the next call to Item_field::fix_fields(), where we would try to use an invalid Name_resolution_context object. Fixed by not creating Name_resolution_context object if the Item_field's context does not belong to the subselect(s) that were flattened.	9 years ago
Igor Babaev	1f2ef57403	Fixed bug mdev-5686. The calls of the function remove_eq_conds() may change the and/or structure of the where conditions. So JOIN::equal_cond should be updated for non-recursive calls of remove_eq_conds().	12 years ago
Igor Babaev	5b441013e1	Fixed bug mdev-5468. The field JOIN::select_lex->where should be updated after the call of remove_eq_conds() in the function make_join_statistics(). This matters for subselects.	12 years ago
Igor Babaev	c0f31dc9f3	Another attempt to fix bug mdev-5103. The earlier pushed fix for the bug was incomplete. It did not remove the main cause of the problem: the function remove_eq_conds() removed always true multiple equalities from any conjunct, but did not adjust the list of them stored in Item_cond_and::cond_equal.current_level. Simplified the test case for the bug and moved it to another test file. The fix triggered changes in EXPLAIN EXTENDED for some queries.	12 years ago
Sergei Golubchik	fcf87600a2	MDEV-4865 Change related to --log option/variable was merged partially Complete the merge of magne.mahre@oracle.com-20101102115354-vxcaxminmzglzalk (WL#5185 Remove deprecated 5.1 features)	12 years ago
Sergey Petrunya	c7020dfd70	Fix a number of trivial test failures by updating error message: "Unknown table tbl" is now "Unknown table database.tbl" (part#3)	13 years ago
Sergey Petrunya	1c6fc3f6b9	[SHOW] EXPLAIN UPDATE/DELETE, code re-structuring Part 2 of: - Pass more tests - select with subselects is now shown with type=PRIMARY where it used to be (incorrectly) 'SIMPLE'	13 years ago
unknown	599a1384af	Fix for MDEV-4144 Analysis: The reason for the inefficent plan was that Item_subselect::is_expensive() didn't detect the special case when a subquery was optimized, but had no join plan because it either has no table, or its tables have been optimized away, or the optimizer detected that the result set is empty. Solution: Identify the special cases above in the Item_subselect::is_expensive(), and consider such degenerate subqueries inexpensive.	13 years ago
unknown	e648ff111a	MDEV-537 Make multi-column non-top level subqueries to be executed via index (index/unique subquery) instead of single_select_engine This task changes the IN-EXISTS rewrite for multi-column subqueries "(a, b) IN (select b, c ...)" to work in the same way as for single-column subqueries "a IN (select b ...) with respect to the injection of NULL-rejecting predicates. More specifically, the method Item_in_subselect::create_row_in_to_exists_cond() adds Item_is_not_null_test and Item_func_trig_cond only if the left IN operand can be NULL. Not having these predicates when not necessary, makes it possible to rewrite the subquery into a "unique_subquery" or "index_subquery" when there is a suitable index on the only subquery table.	13 years ago
unknown	2255132f20	MDEV-4056 fix. The problem was that maybe_null of Item_row and its componetes was unsynced after update_used_tables() (and so pushed_cond_guards was not initialized but then requested). Fix updates Item_row::maybe_null on update_used_tables().	13 years ago
unknown	e99aa91e90	MDEV-3928: Assertion `example' failed in Item_cache::is_expensive_processor with a 2-level IN subquery Analysis: The following call stack shows that it is possible to set Item_cache::value_cached, and the relevant value without setting Item_cache::example. #0 Item_cache_temporal::store_packed at item.cc:8395 #1 get_datetime_value at item_cmpfunc.cc:915 #2 resolve_const_item at item.cc:7987 #3 propagate_cond_constants at sql_select.cc:12264 #4 propagate_cond_constants at sql_select.cc:12227 #5 optimize_cond at sql_select.cc:13026 #6 JOIN::optimize at sql_select.cc:1016 #7 st_select_lex::optimize_unflattened_subqueries at sql_lex.cc:3161 #8 JOIN::optimize_unflattened_subqueries at opt_subselect.cc:4880 #9 JOIN::optimize at sql_select.cc:1554 The fix is to set Item_cache_temporal::example even when the value is set directly by Item_cache_temporal::store_packed. This makes the Item_cache_temporal object consistent.	13 years ago
unknown	a8bad7d900	MDEV-3902 Assertion `record_length == m_record_length' failed at Filesort_buffer::alloc_sort_buffer This bug is a duplicate of mdev-3899 so adding a test case only.	13 years ago
unknown	1b2692d0e9	MDEV-3899 Valgrind warnings (blocks are definitely lost) in filesort on IN subquery with SUM and DISTINCT Analysys: In the beginning of JOIN::cleanup there is code that is supposed to free all filesort buffers. The code assumes that the table being sorted is the first non-constant table. To get this table it calls: first_top_level_tab(this, WITHOUT_CONST_TABLES) However, first_top_level_tab() instead returned the wrong table - the first one in the plan, instead of the first non-constant table. There is no other place outside filesort() where sort buffers may be freed. As a result, the sort buffer was not freed, and there was a memory leak. Solution: Change first_top_level_tab(), to test for WITH_CONST_TABLES instead of WITHOUT_CONST_TABLES.	13 years ago
unknown	b917fb63a6	Fix bug lp:1009187, mdev-373, mysql bug#58628 Analysis: The queries in question use the [unique \| index]_subquery execution methods. These methods reuse the ref keys constructed by create_ref_for_key(). The way create_ref_for_key() works is that it doesn't store in ref.key_copy[] store_key elements that represent constants. In particular it doesn't store the store_key for NULL constants. The execution of [unique \| index]_subquery calls subselect_uniquesubquery_engine::copy_ref_key, which in addition to copy the left IN argument into a index lookup key, is supposed to detect if the left IN argument contains NULLs. Since the store_key for the NULL constant is not copied into the key array, the null is not detected, and execution erroneously proceeds as if it should look for a complete match. Solution: The solution (unlike MySQL) is to reuse already computed information about NULL presence. Item_in_optimizer::val_int already finds out if the left IN operand contains NULLs. The fix propagates this to the execution methods subselect_[unique \| index]subquery_engine::exec so it knows if there were NULL values independent of the presence of keys. In addition the patch siplifies copy_ref_key() and the logic that hanldes the case of NULLs in the left IN operand.	13 years ago
Sergey Petrunya	55597a4869	MDEV-410: EXPLAIN shows type=range, while SHOW EXPLAIN and userstat show full table scan is used - Make Item_subselect::fix_fields() ignore UNCACHEABLE_EXPLAIN flag when deciding whether the subquery item should be marked as constant.	14 years ago
unknown	88d3d853f4	Fix bug lp:1008773 Analysis: Queries with implicit grouping (there is aggregate, but no group by) follow some non-obvious semantics in the case of empty result set. Aggregate functions produce some special "natural" value depending on the function. For instance MIN/MAX return NULL, COUNT returns 0. The complexity comes from non-aggregate expressions in the select list. If the non-aggregate expression is a constant, it can be computed, so we should return its value, however if the expression is non-constant, and depends on columns from the empty result set, then the only meaningful value is NULL. The cause of the wrong result was that for subqueries the optimizer didn't make a difference between constant and non-constant ones in the case of empty result for implicit grouping. Solution: In all implementations of Item_subselect::no_rows_in_result() check if the subquery predicate is constant. If it is constant, do not set it to the default value for implicit grouping, instead let it be evaluated.	14 years ago
unknown	f1ab00891a	Fixed bug lp:1000649 Analysis: When the method JOIN::choose_subquery_plan() decided to apply the IN-TO-EXISTS strategy, it set the unit and select_lex uncacheable flag to UNCACHEABLE_DEPENDENT_INJECTED unconditionally. As result, even if IN-TO-EXISTS injected non-correlated predicates, the subquery was still treated as correlated. Solution: Set the subquery as correlated only if the injected predicate(s) depend on the outer query.	14 years ago
Michael Widenius	83c02f3237	Increased the version number to 10.0 - Fixed code that was not ready for a major version number > 9 - Fixed test cases that assumed max major version number could be 9 Updated version number for depricated options (will be removed in a later commit) VERSION: Version number 10.0.0 client/mysqlbinlog.cc: Added support for major version numbers > 9 cmake/mysql_version.cmake: Added support for version numbers that is 0 mysql-test/r/comments.result: Modified test to handle version number 100000 mysql-test/r/func_system.result: Modified test to handle version number 100000 mysql-test/r/log_state.result: Updated depricated error message mysql-test/r/sp.result: Modified test to handle version number 100000 mysql-test/r/subselect4.result: Updated depricated error message mysql-test/r/variables.result: Updated depricated error message mysql-test/suite/rpl/r/rpl_conditional_comments.result: Modified test to handle version number 100000 mysql-test/suite/rpl/r/rpl_loaddatalocal.result: Modified test to handle version number 100000 mysql-test/suite/rpl/t/rpl_conditional_comments.test: Modified test to handle version number 100000 mysql-test/suite/rpl/t/rpl_loaddatalocal.test: Modified test to handle version number 100000 mysql-test/suite/sys_vars/r/debug_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/engine_condition_pushdown_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/log_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/log_slow_queries_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/multi_range_count_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/rpl_recovery_rank_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/sql_big_selects_func.result: Updated depricated error message mysql-test/suite/sys_vars/r/sql_max_join_size_basic.result: Updated depricated error message mysql-test/suite/sys_vars/r/sql_max_join_size_func.result: Updated depricated error message mysql-test/t/comments.test: Modified test to handle version number 100000 mysql-test/t/file_contents.test: Modified test to handle version number 100000 mysql-test/t/func_system.test: Modified test to handle version number 100000 mysql-test/t/parser_not_embedded.test: Modified test to handle version number 100000 mysql-test/t/sp.test: Modified test to handle version number 100000 sql/mysqld.cc: Updated version number for depricated options (will be removed in a later commit) sql/slave.cc: Modified test to handle version number 100000 Better error messages sql/sql_lex.cc: Modified test to handle version number 100000 in comment syntax sql/sys_vars.cc: Updated version number for depricated options (will be removed in a later commit)	14 years ago
unknown	941018f8d1	Patch for mdev-287: CHEAP SQ: A query with subquery in SELECT list, EXISTS, inner joins takes hundreds times longer Analysis: The fix for lp:944706 introduces early subquery optimization. While a subquery is being optimized some of its predicates may be removed. In the test case, the EXISTS subquery is constant, and is evaluated to TRUE. As a result the whole OR is TRUE, and thus the correlated condition "b = alias1.b" is optimized away. The subquery becomes non-correlated. The subquery cache is designed to work only for correlated subqueries. If constant subquery optimization is disallowed, then the constant subquery is not evaluated, the subquery remains correlated, and its execution is cached. As a result execution is fast. However, when the constant subquery was optimized away, it was neither cached by the subquery cache, nor it was cached by the internal subquery caching. The latter was due to the fact that the subquery still appeared as correlated to the subselect_XYZ_engine::exec methods, and they re-executed the subquery on each call to Item_subselect::exec. Solution: The solution is to update the correlated status of the subquery after it has been optimized. This status consists of: - st_select_lex::is_correlated - Item_subselect::is_correlated - SELECT_LEX::uncacheable - SELECT_LEX_UNIT::uncacheable The status is updated by st_select_lex::update_correlated_cache(), and its caller st_select_lex::optimize_unflattened_subqueries. The solution relies on the fact that the optimizer already called st_select_lex::update_used_tables() for each subquery. This allows to efficiently update the correlated status of each subquery without walking the whole subquery tree. Notice that his patch is an improvement over MySQL 5.6 and older, where subqueries are not pre-optimized, and the above analysis is not possible.	14 years ago
unknown	da5214831d	Fix for bug lp:944706, task MDEV-193 The patch enables back constant subquery execution during query optimization after it was disabled during the development of MWL#89 (cost-based choice of IN-TO-EXISTS vs MATERIALIZATION). The main idea is that constant subqueries are allowed to be executed during optimization if their execution is not expensive. The approach is as follows: - Constant subqueries are recursively optimized in the beginning of JOIN::optimize of the outer query. This is done by the new method JOIN::optimize_constant_subqueries(). This is done so that the cost of executing these queries can be estimated. - Optimization of the outer query proceeds normally. During this phase the optimizer may request execution of non-expensive constant subqueries. Each place where the optimizer may potentially execute an expensive expression is guarded with the predicate Item::is_expensive(). - The implementation of Item_subselect::is_expensive has been extended to use the number of examined rows (estimated by the optimizer) as a way to determine whether the subquery is expensive or not. - The new system variable "expensive_subquery_limit" controls how many examined rows are considered to be not expensive. The default is 100. In addition, multiple changes were needed to make this solution work in the light of the changes made by MWL#89. These changes were needed to fix various crashes and wrong results, and legacy bugs discovered during development.	14 years ago
Sergei Golubchik	54f9fe6c8b	lp:938977 - Query performance with join/index super slow on MariaDB 5.3.4RC make sure that stored routines are evaluated (that is, de facto - cached) in convert_const_to_int(). revert the fix for lp:806943 because it cannot be repeated anymore. add few tests for convert_const_to_int()	14 years ago
Igor Babaev	841a74a4d6	Fixed LP bug #939009 . The result of materialization of the right part of an IN subquery predicate is placed into a temporary table. Each row of the materialized table is distinct. A unique key over all fields of the temporary table is defined and created. It allows to perform key look-ups into the table. The table created for a materialized subquery can be accessed by key as any other table. The function best_access-path search for the best access to join a table to a given partial join. With some where conditions this function considers a possibility of a ref_or_null access. If such access employs the unique key on the temporary table then when estimating the cost this access the function tries to use the array rec_per_key. Yet, such array is not built for this unique key. This causes a crash of the server. Rows returned by the subquery that contain nulls don't have to be placed into temporary table, as they cannot be match any row produced by the left part of the subquery predicate. So all fields of the temporary table can be defined as non-nullable. In this case any ref_or_null access to the temporary table does not make any sense and it does not make sense to estimate such an access. The fix makes sure that the temporary table for a materialized IN subquery is defined with columns that are all non-nullable. The also ensures that any row with nulls returned by the subquery is not placed into the temporary table.	14 years ago
Sergey Petrunya	914245ccd8	BUG#934597: Assertion `! is_set()' failed in Diagnostics_area::set_ok_status(THD... - After the exec_const_cond->val_int() call, check for error and return. (if we don't do it, we will eventually hit an error when trying to set status OK in the diagnostics area, which already has an error status).	14 years ago
Igor Babaev	2b1f0b8757	Back-ported the patch of the mysql-5.6 code line that 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.	14 years ago
unknown	072073c09e	Backport of WL#5953 from MySQL 5.6 The patch differs from the original MySQL patch as follows: - All test case differences have been reviewed one by one, and care has been taken to restore the original plan so that each test case executes the code path it was designed for. - A bug was found and fixed in MariaDB 5.3 in Item_allany_subselect::cleanup(). - ORDER BY is not removed because we are unsure of all effects, and it would prevent enabling ORDER BY ... LIMIT subqueries. - ref_pointer_array.m_size is not adjusted because we don't do array bounds checking, and because it looks risky. Original comment by Jorgen Loland: ------------------------------------------------------------- WL#5953 - Optimize away useless subquery clauses For IN/ALL/ANY/SOME/EXISTS subqueries, the following clauses are meaningless: * ORDER BY (since we don't support LIMIT in these subqueries) * DISTINCT * GROUP BY if there is no HAVING clause and no aggregate functions This WL detects and optimizes away these useless parts of the query during JOIN::prepare()	14 years ago
Igor Babaev	7a1406f229	Fixed LP bug #904832 . Do not perform index condition pushdown for conditions containing subqueries and stored functions.	14 years ago
Igor Babaev	f5dac20f38	Made the optimizer switch flags 'outer_join_with_cache', 'semijoin_with_cache' set to 'on' by default.	14 years ago
Sergei Golubchik	2ccf247e93	after merge changes: * rename all debugging related command-line options and variables to start from "debug-", and made them all OFF by default. * replace "MySQL" with "MariaDB" in error messages * "Cast ... converted ... integer to it's ... complement" is now a note, not a warning * @@query_cache_strip_comments now has a session scope, not global.	14 years ago
Sergey Petrunya	ae480437ce	Small semi-join optimization improvement: - if we're considering FirstMatch access with one inner table, and @@optimizer_switch has semijoin_with_cache flag, calculate costs as if we used join cache (because we will be able to do so)	14 years ago
Sergey Petrunya	255fd6c929	Make subquery Materialization, as well as semi-join Materialization be shown 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.	14 years ago
Igor Babaev	b4b7d941fe	Fixed LP bug #889750 . 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.	14 years ago
unknown	511459bd14	Enable subquery materialization=ON by default.	14 years ago
Sergey Petrunya	47861a6577	Change the default @@optimizer_switch settings: - semijoin=on - firstmatch=on - loosescan=on	14 years ago
unknown	6498687325	Fix bug lp:833702 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.	14 years ago
Igor Babaev	2162704829	Moved the test case for bug 879939 to derived_view.test where it belongs to.	14 years ago
Michael Widenius	fa36a7426b	Fixed lp:879939 "assertion in ha_maria::enable_indexes with derived_with_keys=on" Honor unique/not unique when creating keys for internal tempory tables. Added new variables to be used to limit how keys are created for internal temporary tables. include/maria.h: Added maria_max_key_length() and maria_max_key_segments() include/myisam.h: Added myisam_max_key_length() and myisam_max_key_segments() mysql-test/r/mysql.result: Drop all used tables mysql-test/r/subselect4.result: Added test case for lp:879939 mysql-test/t/mysql.test: Drop all used tables mysql-test/t/subselect4.test: Added test case for lp:879939 sql/mysql_priv.h: Added internal_tmp_table_max_key_length and internal_tmp_table_max_key_segments to be used to limit how keys for derived tables are created. sql/mysqld.cc: Added internal_tmp_table_max_key_length and internal_tmp_table_max_key_segments to be used to limit how keys for derived tables are created. sql/share/errmsg.txt: Added new error message for internal errors sql/sql_select.cc: Give error if we try to create a wrong key (this error should never happen) Honor unique/not unique when creating keys for internal tempory tables. storage/maria/ha_maria.cc: Added change_table_ptr() to ensure that external_ref points always to the correct table. (Not having this caused an assert in the included test) storage/maria/ha_maria.h: Added change_table_ptr() to ensure that external_ref points always to the correct table. storage/maria/ma_check.c: Fixed bug in Duplicate key error printing (now row position is printed correctly) storage/maria/ma_create.c: maria_max_key_length() -> _ma_max_key_length() storage/maria/ma_info.c: Added extern function maria_max_key_length() to calculate the max key length based on current block size. storage/maria/ma_open.c: maria_max_key_length() -> _ma_max_key_length() storage/maria/maria_def.h: maria_max_key_length() -> _ma_max_key_length() storage/myisam/ha_myisam.cc: Added change_table_ptr() to ensure that external_ref points always to the correct table. (Not having this caused an assert in the included test) storage/myisam/ha_myisam.h: Added change_table_ptr() to ensure that external_ref points always to the correct table.	14 years ago
Sergey Petrunya	acf27225b5	Post-merge fixes: - Fix derived_view.test to work, and enable it - Let subselect*.test do "DROP TABLE IF EXISTS" before they attempt to create the table.	14 years ago
Sergei Golubchik	72e144a470	Sergey Petrunya fixes for subselect* tests, and other misc test fixes	14 years ago
unknown	54caeee5d6	Making subquery cache on by default.	14 years ago
Michael Widenius	64d6cbe556	Removed duplicate test	14 years ago
unknown	c1a6dbe5b2	Fixed bug lp:825018 Analysis: During the first execution of the query through the stored procedure, the optimization phase calls substitute_for_best_equal_field(), which calls Item_in_optimizer::transform(). The latter replaces Item_in_subselect::left_expr with args[0] via assignment. In this test case args[0] is an Item_outer_ref which is created/deallocated for each re-execution. As a result, during the second execution Item_in_subselect::left_expr pointed to freed memory, which resulted in a crash. Solution: The solution is to use change_item_tree(), so that the origianal left expression is restored after each execution.	14 years ago
unknown	c9e236828e	Fix bug lp:782305 Analysis: Both the wrong result and the valgrind warning were a result of incomplete cleanup of the MIN/MAX subquery rewrite. At the first execution of the query, the non-aggregate subquery is transformed into an aggregate MIN/MAX subquery. During the fix_fields phase of the MIN/MAX function, it sets the property st_select_lex::with_sum_func to true. The second execution of the query finds this flag to be ON. When optimization reaches the same MIN/MAX subquery transformation, it tests if the subquery is an aggregate or not. Since select_lex->with_sum_func == true from the previous execution, the transformation executes the second branch that handles aggregate subqueries. This substitutes the subquery Item into a Item_maxmin_subselect. At the same time elsewhere it is assumed that the subquery Item is of type Item_allany_subselect. Ultimately this results in casting the actual object to the wrong class, and calling the wrong any_value() method from empty_underlying_subquery(). Solution: Cleanup the st_select_lex::with_sum_func property in the case when the MIN/MAX transformation was performed for a non-aggregate subquery, so that the transformation can be repeated.	15 years ago
unknown	af284b55f0	Make subquery cache off by default. mysql-test/r/subselect_scache.result: Test with subquery cache on. mysql-test/t/subselect_scache.test: Test with subquery cache on.	15 years ago
unknown	53681ee5db	Fix bug lp:777691 Analysis: For some of the re-executions of the correlated subquery the where clause is false. In these cases the execution of the subquery detects that it must generate a NULL row because of implicit grouping. In this case the subquery execution reaches the following code in do_select(): while ((table= li++)) mark_as_null_row(table->table); This code marks all rows in the table as complete NULL rows. In the example, when evaluating the field t2.f10 for the second row, all bits of Field::null_ptr[0] are set by the previous call to mark_as_null_row(). Then the call to Field::is_null() returns true, resulting in a NULL for the MAX function. Thus the lines above are not suitable for subquery re-execution because mark_as_null_row() changes the NULL bits of each table field, and there is no logic to restore these fields. Solution: The call to mark_as_null_row() was added by the fix for bug lp:613029. Therefore removing the fix for lp:613029 corrects this wrong result. At the same time the test for lp:613029 behaves correctly because the changes of MWL#89 result in a different execution path where: - the constant subquery is evaluated via JOIN::exec_const_cond - detecting that it has an empty result triggers the branch if (zero_result_cause) return_zero_rows() - return_zero_rows() calls mark_as_null_row().	15 years ago
Sergey Petrunya	85571ea76c	Disable LooseScan and FirstMatch when outer joins are present.	15 years ago
Sergey Petrunya	1492de8563	Set the default to be mrr=off,mrr_sort_keys=off: - 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	15 years ago
unknown	e98aecc2e0	Test for bug lp:611382 The bug itself has been fixed by MWL#89.	15 years ago

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178 Commits (8d75a7533ee80efa5275a058dfadf8947e5857a6)