mariadb

Tree: b33826e555

Author	SHA1	Message	Date
Sergey Petrunya	b33826e555	MWL#90, code cleanup - Unify EXPLAIN printout for <subqueryN> tables with regular tables - Update test results for <subqueryN> tables: s/unique_key/distinct_key/g s/1.0/100.0/ for "filtered" column	16 years ago
Sergey Petrunya	0cc3724697	MWL#90: Subqueries: Inside-out execution for non-semijoin materialized subqueries that are AND-parts of the WHERE - Change "SUBQUERY#n" to "<subquery{n}>" in EXPLAIN output. We need to it to be lowercase so that EXPLAIN results do not differ in case between systems with case-sensitive and case-insensitive filesystems. - Remove garbage comments, add better comments.	16 years ago
Sergey Petrunya	30bac79806	Always refer to materialized table as "SUBSELECT#%d" where %d is select number - for Item-based materialization, it was "materialized subselect" - for SJ-Materialization it was "subquery%d"	16 years ago
Sergey Petrunya	8a06a7e3a7	MWL#110: Make EXPLAIN always show materialization separately - Add Item_in_subselect::get_identifier() that returns subquery's id - Change select_describe() to produce output in new format - Update test results (checked)	16 years ago
Sergey Petrunya	47d0cf2929	Apply fix by Roy Lyseng: Bug#48623: Multiple subqueries are optimized incorrectly The function setup_semijoin_dups_elimination() has a major loop that goes through every table in the JOIN object. Usually, there is a normal "plus one" increment in the for loop that implements this, but each semijoin nest is treated as one entity and there is another increment that skips past the semijoin nest to the next table in the JOIN object. However, when combining these two increments, the next joined table is skipped, and if that happens to be the start of another semijoin nest, the correct processing for that nest will not be carried out. mysql-test/r/subselect_sj.result: Added test results for bug#48623 mysql-test/r/subselect_sj_jcl6.result: Added test results for bug#48623 mysql-test/t/subselect_sj.test: Added test case for bug#48623 sql/opt_subselect.cc: Omitted the "plus one" increment in the for loop, added "plus one" in the remaining switch case, fixed coding style issue in remaining increment operations.	16 years ago
Sergey Petrunya	77e66c6985	BUG#43768: Prepared query with nested subqueries core dumps on second execution Fix two problems: 1. Let optimize_semijoin_nests() reset sj_nest->sjmat_info irrespectively of value of optimizer_flag. We need this in case somebody has turned optimization off between reexecutions of the same statement. 2. Do not pull out constant tables out of semi-join nests. The problem is that pullout operation is not undoable, and if a table is constant because it is 1/0-row table it may cease to be constant on the next execution. Note that tables that are constant because of possible eq_ref(const) access will still be pulled out as they are considered functionally-dependent.	16 years ago
Sergey Petrunya	ea982e336d	Apply fix by oystein.grovlen@sun.com 2010-03-12: Bug#48213 Materialized subselect crashes if using GEOMETRY type The problem occurred because during semi-join a materialized table was created which contained a GEOMETRY column, which is a specialized BLOB column. This caused an segmentation fault because such tables will have extra columns, and the semi-join code was not prepared for that. The solution is to disable materialization when Blob/Geometry columns would need to be materialized. Blob columns cannot be used for index look-up anyway, so it does not makes sense to use materialization. This fix implies that it is detected earlier that subquery materialization can not be used. The result of that is that in->exist optimization may be performed for such queries. Hence, extended query plans for such queries had to be updated. mysql-test/r/subselect_mat.result: Update extended query plan for subqueries that cannot use materialization due to Blobs. mysql-test/r/subselect_sj.result: Updated result file. mysql-test/r/subselect_sj_jcl6.result: Update result file. mysql-test/t/subselect_sj.test: Add test case for Bug#48213 that verifies that semi-join works when subquery select list contain Blob columns. Also verify that materialization is not used. sql/opt_subselect.cc: Disable materialization for semi-join/subqueries when the subquery select list contain Blob columns.	16 years ago
Sergey Petrunya	02e9fa62e7	BUG#45174: XOR in subqueries produces differing results in 5.1 and 5.4 BUG#50019: Wrong result for IN-subquery with materialization - Fix equality substitution in presense of semi-join materialization, lookup and scan variants (started off from fix by Evgen Potemkin, then modified it to work in all cases)	16 years ago
unknown	3d2a74609a	MWL#68 Subquery optimization: Efficient NOT IN execution with NULLs This patch does three things: - It adds the possibility to force the execution of top-level [NOT] IN subquery predicates via the IN=>EXISTS transformation. This is done by setting both optimizer switches partial_match_rowid_merge and partial_match_table_scan to "off". - It adjusts all test cases where the complete optimizer_switch is selected because now we have two more switches. - For those test cases where the plan changes because of the new available strategies, we switch off both partial match strategies in order to force the "old" IN=>EXISTS strategy. This is done because most of these test cases specifically test bugs in this strategy. sql/opt_subselect.cc: Adds the possibility to force the execution of top-level [NOT] IN subquery predicates via the IN=>EXISTS transformation. This is done by setting both optimizer switches partial_match_rowid_merge and partial_match_table_scan to "off".	16 years ago
Sergey Petrunya	c2924e155e	BUG#49129: Wrong result with IN-subquery with join_cache_level=6 and firstmatch=off - The problem was that DuplicateWeedout strategy setup code wasn't aware of the fact that join buffering will be used and applied optimization that doesn't work together with join buffering. Fixed by making DuplicateWeedout setup code to have a pessimistic check about whether there is a chance that join buffering will be used. - Make JOIN_CACHE_BKA::init() correctly process Copy_field elements that denote saving current rowids in the join buffer. mysql-test/r/subselect_sj2.result: Update test results mysql-test/r/subselect_sj2_jcl6.result: Update test results mysql-test/r/subselect_sj_jcl6.result: Testcase mysql-test/t/subselect_sj2.test: Update test results mysql-test/t/subselect_sj_jcl6.test: Testcase sql/opt_subselect.cc: - The problem was that DuplicateWeedout strategy setup code wasn't aware of the fact that join buffering will be used and applied optimization that doesn't work together with join buffering. Fixed by making DuplicateWeedout setup code to have a pessimistic check about whether there is a chance that join buffering will be used. sql/sql_join_cache.cc: Make JOIN_CACHE_BKA::init() correctly process Copy_field elements that denote saving current rowids in the join buffer. sql/sql_select.cc: Added a question note	16 years ago
Igor Babaev	3ccc1d6b1e	Corrected Evgen's fix for bug #45191 . Made sure that join buffers could be used for inner tables of any semi-join when the first match strategy is employed.	16 years ago
Sergey Petrunya	0e7c84153d	Bug#49198 Wrong result for second call of of procedure with view in subselect. Re-worked fix of Tor Didriksen: The problem was that fix_after_pullout() after semijoin conversion wasn't propagated from the view to the underlying table. On subesequent executions of the prepared statement, we would mark the underlying table as 'dependent' and the predicate anlysis would lead to a different (and illegal) execution plan.	16 years ago
Sergey Petrunya	0cf5145dee	Fix buildbot failure: take into account that there is no optimizer_switch flag for table elimination in debug builds. (part 2)	16 years ago
Sergey Petrunya	3ffa889184	Fix buildbot failure: take into account that there is no optimizer_switch flag for table elimination in debug builds.	16 years ago
Sergey Petrunya	663773aa8c	Subquery backport: - More test results updates (checked)	16 years ago
Sergey Petrunya	f4d5521043	BUG#31480: Incorrect result for nested subquery when executed via semi join - Variant #3 of the fix. It also = Unifies code with table elimination's = is able to handle FROM-subquery pullout.	16 years ago
Sergey Petrunya	b83cb52e9e	Backport of subquery optimizations to 5.3. There are still test failures because of: - Wrong query results in outer join + semi join - EXPLAIN output differences	16 years ago

19 Commits (b33826e5552d3659d66da70926749bb121c3dce0)