March 2016 - developers - lists.mariadb.org

[Maria-developers] main.delayed fails on timeout
by Alexander Barkov 03 Mar '16

03 Mar '16

Hello Monty, Sergei, Can you please have a look into: http://buildbot.askmonty.org/buildbot/builders/kvm-deb-precise-amd64/builds… Can you please give any suggestions about what we can do to fix the problem with main.delayed failing sporadically? This problem is blocking us badly in Debian. Otto can try to disable this test temporary. But it would be nice to have a real fix. Any tips would be very appreciated. Thanks!

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[Maria-developers] GSoC 2015 mysqlbinlog Enhancement.
by Rebecca Tucker 03 Mar '16

03 Mar '16

Hello everyone, I am Rebecca Tucker a MS student at University of Maryland and I wish to participate in the summer of code to work on making the mysqlbinlog tool to understand global transaction IDs. I am familiar with the tool and replication and can write documented C and C++ code. I Look forward to communicating with you soon to get more pointers on the project. Cheers, Becca.

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[Maria-developers] GSOC 2016 self Introduction
by Tapan Halani 02 Mar '16

02 Mar '16

Hello all devs, I am Tapan Halani , an undergrad student from India. I am interested in contributing code to MariaDB and am taking part in GSoC 2016 also. I have already done all the prerequisite code cloning and setup etc. and am going through MDEV-4989 , trying to understand and solve it. Looking forward to have a great time contributing. Thanks Tapan

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[Maria-developers] Igor please review: b6a2441: Remove all comments starting with 'psergey'
by Sergey Petrunia 02 Mar '16

02 Mar '16

Please review the below: ----- Forwarded message from Sergei Petrunia <psergey(a)askmonty.org> ----- Date: Wed, 2 Mar 2016 13:35:11 +0300 (FET) From: Sergei Petrunia <psergey(a)askmonty.org> To: commits(a)mariadb.org, sergey(a)mariadb.com Subject: b6a2441: Remove all comments starting with 'psergey' revision-id: b6a2441edf3bfce381f5dc24f5be23fce9ac36dd parent(s): b05158cc10a75196b5c0bf8dad9360608a2dd5b9 committer: Sergei Petrunia branch nick: 10.1-dbg5 timestamp: 2016-03-02 13:35:11 +0300 message: Remove all comments starting with 'psergey' --- sql/item.cc | 3 +-- sql/item_subselect.cc | 15 +-------------- sql/opt_range.cc | 4 ++-- sql/opt_subselect.cc | 1 - sql/opt_table_elimination.cc | 2 -- sql/sql_base.cc | 4 ++-- sql/sql_join_cache.cc | 7 +------ sql/sql_select.cc | 39 ++------------------------------------- sql/sql_statistics.cc | 9 --------- sql/sql_union.cc | 2 +- 10 files changed, 10 insertions(+), 76 deletions(-) diff --git a/sql/item.cc b/sql/item.cc index d6132cc..8fd45d5 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -4227,8 +4227,7 @@ static bool mark_as_dependent(THD *thd, SELECT_LEX *last, SELECT_LEX *current, DBUG_PRINT("info", ("mark_item: %p lex: %p", mark_item, last)); mark_item->depended_from= last; } - if (current->mark_as_dependent(thd, last, - /** resolved_item psergey-thu **/ mark_item)) + if (current->mark_as_dependent(thd, last, mark_item)) DBUG_RETURN(TRUE); if (thd->lex->describe & DESCRIBE_EXTENDED) { diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc index a5ef81e..e11eafe 100644 --- a/sql/item_subselect.cc +++ b/sql/item_subselect.cc @@ -243,10 +243,6 @@ bool Item_subselect::fix_fields(THD *thd_param, Item **ref) done_first_fix_fields= TRUE; inside_first_fix_fields= TRUE; upper_refs.empty(); - /* - psergey-todo: remove _first_fix_fields calls, we need changes on every - execution - */ } eliminated= FALSE; @@ -1753,7 +1749,6 @@ my_decimal *Item_in_subselect::val_decimal(my_decimal *decimal_value) Check that the right part of the subselect contains no more than one column. E.g. in SELECT 1 IN (SELECT * ..) the right part is (SELECT * ...) */ - // psergey: duplicated_subselect_card_check if (select_lex->item_list.elements > 1) { my_error(ER_OPERAND_COLUMNS, MYF(0), 1); @@ -2172,7 +2167,6 @@ bool Item_allany_subselect::is_maxmin_applicable(JOIN *join) DBUG_ENTER("Item_in_subselect::row_value_transformer"); - // psergey: duplicated_subselect_card_check if (select_lex->item_list.elements != cols_num) { my_error(ER_OPERAND_COLUMNS, MYF(0), cols_num); @@ -3600,7 +3594,6 @@ void subselect_engine::set_row(List<Item> &item_list, Item_cache **row) if (!(row[i]= Item_cache::get_cache(thd, sel_item, sel_item->cmp_type()))) return; row[i]->setup(thd, sel_item); - //psergey-backport-timours: row[i]->store(sel_item); } if (item_list.elements > 1) cmp_type= res_type= ROW_RESULT; @@ -4017,9 +4010,6 @@ int subselect_uniquesubquery_engine::index_lookup() subselect_uniquesubquery_engine::~subselect_uniquesubquery_engine() { - /* Tell handler we don't need the index anymore */ - //psergey-merge-todo: the following was gone in 6.0: - //psergey-merge: don't need this after all: tab->table->file->ha_index_end(); } @@ -4172,9 +4162,6 @@ int subselect_indexsubquery_engine::exec() uint subselect_single_select_engine::cols() { - //psergey-sj-backport: the following assert was gone in 6.0: - //DBUG_ASSERT(select_lex->join != 0); // should be called after fix_fields() - //return select_lex->join->fields_list.elements; return select_lex->item_list.elements; } @@ -5136,7 +5123,7 @@ void check_out_index_stats(JOIN *join) table_map key_used=0; table_map non_key_used= 0; - bzero(&key_start_use, sizeof(key_start_use)); //psergey-todo: safe initialization! + bzero(&key_start_use, sizeof(key_start_use)); bzero(&key_infix_use, sizeof(key_infix_use)); for (order= join->group_list; order; order= order->next) diff --git a/sql/opt_range.cc b/sql/opt_range.cc index ed7e9a5..72a851d 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -8640,7 +8640,7 @@ static bool remove_nonrange_trees(RANGE_OPT_PARAM *param, SEL_TREE *tree) if (key1->elements != 1) { - key2->use_count+=key1->elements-1; //psergey: why we don't count that key1 has n-k-p? + key2->use_count+=key1->elements-1; key2->increment_use_count((int) key1->elements-1); } if (key1->type == SEL_ARG::MAYBE_KEY) @@ -10104,7 +10104,7 @@ ha_rows check_quick_select(PARAM *param, uint idx, bool index_only, } DBUG_PRINT("exit", ("Records: %lu", (ulong) rows)); - DBUG_RETURN(rows); //psergey-merge:todo: maintain first_null_comp. + DBUG_RETURN(rows); } diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc index cb356fb..1a13dd6 100644 --- a/sql/opt_subselect.cc +++ b/sql/opt_subselect.cc @@ -635,7 +635,6 @@ int check_and_do_in_subquery_rewrites(JOIN *join) (oe1, oe2) IN (SELECT ie1, ie2, ie3 ...) TODO why do we have this duplicated in IN->EXISTS transformers? - psergey-todo: fix these: grep for duplicated_subselect_card_check */ if (select_lex->item_list.elements != in_subs->left_expr->cols()) { diff --git a/sql/opt_table_elimination.cc b/sql/opt_table_elimination.cc index 912ef4a..8378e8e 100644 --- a/sql/opt_table_elimination.cc +++ b/sql/opt_table_elimination.cc @@ -757,8 +757,6 @@ void eliminate_tables(JOIN *join) else { DBUG_ASSERT(!tbl->nested_join || tbl->sj_on_expr); - //psergey-todo: is the following really correct or we'll need to descend - //down all ON clauses: ? if (tbl->sj_on_expr) tables_used_on_left |= tbl->sj_on_expr->used_tables(); } diff --git a/sql/sql_base.cc b/sql/sql_base.cc index ac2162b..3d02f9c 100644 --- a/sql/sql_base.cc +++ b/sql/sql_base.cc @@ -3965,7 +3965,7 @@ thr_lock_type read_lock_type_for_table(THD *thd, goto end; } DBUG_PRINT("tcache", ("opening table: '%s'.'%s' item: %p", - tables->db, tables->table_name, tables)); //psergey: invalid read of size 1 here + tables->db, tables->table_name, tables)); (*counter)++; /* @@ -8105,7 +8105,7 @@ bool setup_tables(THD *thd, Name_resolution_context *context, Item *item= table_list->jtbm_subselect->optimizer; if (table_list->jtbm_subselect->optimizer->fix_fields(thd, &item)) { - my_error(ER_TOO_MANY_TABLES,MYF(0), static_cast<int>(MAX_TABLES)); /* psergey-todo: WHY ER_TOO_MANY_TABLES ???*/ + my_error(ER_TOO_MANY_TABLES,MYF(0), static_cast<int>(MAX_TABLES)); DBUG_RETURN(1); } DBUG_ASSERT(item == table_list->jtbm_subselect->optimizer); diff --git a/sql/sql_join_cache.cc b/sql/sql_join_cache.cc index f84440a..9f69169 100644 --- a/sql/sql_join_cache.cc +++ b/sql/sql_join_cache.cc @@ -3919,11 +3919,6 @@ int JOIN_TAB_SCAN_MRR::next() If a record in in an incremental cache contains no fields then the association for the last record in cache will be equal to cache->end_pos */ - /* - psergey: this makes no sense where HA_MRR_NO_ASSOC is used. - DBUG_ASSERT(cache->buff <= (uchar *) (*ptr) && - (uchar *) (*ptr) <= cache->end_pos); - */ if (join_tab->table->vfield) update_virtual_fields(join->thd, join_tab->table); } @@ -4591,7 +4586,7 @@ bool JOIN_CACHE_BKAH::prepare_look_for_matches(bool skip_last) { last_matching_rec_ref_ptr= next_matching_rec_ref_ptr= 0; if (no_association && - !(curr_matching_chain= get_matching_chain_by_join_key())) //psergey: added '!' + !(curr_matching_chain= get_matching_chain_by_join_key())) return 1; last_matching_rec_ref_ptr= get_next_rec_ref(curr_matching_chain); return 0; diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 4759af0..878cb8b 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -2861,9 +2861,6 @@ void JOIN::exec_inner() /* Free first data from old join */ - /* - psergey-todo: this is the place of pre-mature JOIN::free call. - */ curr_join->join_free(); if (curr_join->make_simple_join(this, curr_tmp_table)) DBUG_VOID_RETURN; @@ -3001,7 +2998,6 @@ void JOIN::exec_inner() curr_join->select_distinct=0; } curr_tmp_table->reginfo.lock_type= TL_UNLOCK; - // psergey-todo: here is one place where we switch to if (curr_join->make_simple_join(this, curr_tmp_table)) DBUG_VOID_RETURN; calc_group_buffer(curr_join, curr_join->group_list); @@ -6646,12 +6642,6 @@ static void choose_initial_table_order(JOIN *join) jtab_sort_func= straight_join ? join_tab_cmp_straight : join_tab_cmp; } - /* - psergey-todo: if we're not optimizing an SJM nest, - - sort that outer tables are first, and each sjm nest follows - - then, put each [sjm_table1, ... sjm_tableN] sub-array right where - WHERE clause pushdown would have put it. - */ my_qsort2(join->best_ref + join->const_tables, join->table_count - join->const_tables, sizeof(JOIN_TAB*), jtab_sort_func, (void*)join->emb_sjm_nest); @@ -9171,7 +9161,6 @@ static bool create_ref_for_key(JOIN *join, JOIN_TAB *j, !(parent->join_tab_reexec= (JOIN_TAB*) thd->alloc(sizeof(JOIN_TAB)))) DBUG_RETURN(TRUE); /* purecov: inspected */ - // psergey-todo: here, save the pointer for original join_tabs. join_tab= parent->join_tab_reexec; table= &parent->table_reexec[0]; parent->table_reexec[0]= temp_table; table_count= top_join_tab_count= 1; @@ -10060,9 +10049,6 @@ bool TABLE_LIST::is_active_sjm() DBUG_ASSERT(inner_tab->table); current_map= inner_tab->table->map; used_tables2|= current_map; - /* - psergey: have put the -1 below. It's bad, will need to fix it. - */ COND *tmp_cond= make_cond_for_table(thd, on_expr, used_tables2, current_map, /*(inner_tab - first_tab)*/ -1, @@ -11070,11 +11056,6 @@ void check_join_cache_usage_for_tables(JOIN *join, ulonglong options, idx, prev_tab); tab->use_join_cache= MY_TEST(tab->used_join_cache_level); - /* - psergey-merge: todo: raise the question that this is really stupid that - we can first allocate a join buffer, then decide not to use it and free - it. - */ if (join->return_tab) { tab= join->return_tab; @@ -15622,12 +15603,6 @@ bool cond_is_datetime_is_null(Item *cond) @retval false cannot be used */ -/* - psergey-todo: this returns false for int_column='1234' (here '1234' is a - constant. Need to discuss this with Bar). - - See also Field::test_if_equality_guaranees_uniqueness(const Item *item); -*/ static bool test_if_equality_guarantees_uniqueness(Item *l, Item *r) { @@ -18293,10 +18268,6 @@ enum_nested_loop_state rc= evaluate_join_record(join, join_tab, error); } - /* - Note: psergey has added the 2nd part of the following condition; the - change should probably be made in 5.1, too. - */ bool skip_over= FALSE; while (rc == NESTED_LOOP_OK && join->return_tab >= join_tab) { @@ -20956,7 +20927,7 @@ uint find_shortest_key(TABLE *table, const key_map *usable_keys) !(table->file->index_flags(best_key, 0, 1) & HA_CLUSTERED_INDEX))) goto use_filesort; - if (select && // psergey: why doesn't this use a quick? + if (select && table->quick_keys.is_set(best_key) && best_key != ref_key) { key_map tmp_map; @@ -24002,11 +23973,7 @@ void JOIN_TAB::save_explain_data(Explain_table_access *eta, eta->type= tab_type; /* Build "possible_keys" value */ - // psergey-todo: why does this use thd MEM_ROOT??? Doesn't this - // break ANALYZE ? thd->mem_root will be freed, and after that we will - // attempt to print the query plan? append_possible_keys(thd->mem_root, eta->possible_keys, table, keys); - // psergey-todo: ^ check for error return code /* Build "key", "key_len", and "ref" */ if (tab_type == JT_NEXT) @@ -24054,8 +24021,6 @@ void JOIN_TAB::save_explain_data(Explain_table_access *eta, eta->hash_next_key.set(thd->mem_root, & table->key_info[index], table->key_info[index].key_length); - // psergey-todo: ^ is the above correct? are we necessarily joining on all - // columns? } if (!key_info) @@ -24211,7 +24176,7 @@ void JOIN_TAB::save_explain_data(Explain_table_access *eta, eta->push_extra(ET_OPEN_FRM_ONLY); else eta->push_extra(ET_OPEN_FULL_TABLE); - /* psergey-note: the following has a bug.*/ + if (table_list->is_table_read_plan->trivial_show_command || (table_list->is_table_read_plan->has_db_lookup_value() && table_list->is_table_read_plan->has_table_lookup_value())) diff --git a/sql/sql_statistics.cc b/sql/sql_statistics.cc index 28e76ae..b22a2ae 100644 --- a/sql/sql_statistics.cc +++ b/sql/sql_statistics.cc @@ -3650,15 +3650,6 @@ double get_column_range_cardinality(Field *field, { double avg_frequency= col_stats->get_avg_frequency(); res= avg_frequency; - /* - psergey-todo: what does check for min_value, max_value mean? - min/max_value are set to NULL in alloc_statistics_for_table() and - alloc_statistics_for_table_share(). Both functions will immediately - call create_min_max_statistical_fields_for_table and - create_min_max_statistical_fields_for_table_share() respectively, - which will set min/max_value to be valid pointers, unless OOM - occurs. - */ if (avg_frequency > 1.0 + 0.000001 && col_stats->min_value && col_stats->max_value) { diff --git a/sql/sql_union.cc b/sql/sql_union.cc index c835083..b369ef0 100644 --- a/sql/sql_union.cc +++ b/sql/sql_union.cc @@ -974,7 +974,7 @@ bool st_select_lex_unit::exec() 1st execution sets certain members (e.g. select_result) to perform subquery execution rather than EXPLAIN line production. In order to reset them back, we re-do all of the actions (yes it is ugly): - */ // psergey-todo: is the above really necessary anymore?? + */ join->init(thd, item_list, fake_select_lex->options, result); saved_error= mysql_select(thd, &fake_select_lex->ref_pointer_array, &result_table_list, ----- End forwarded message ----- -- BR Sergei -- Sergei Petrunia, Software Developer MariaDB Corporation | Skype: sergefp | Blog: http://s.petrunia.net/blog

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[Maria-developers] GSoC 2016 self Introduction
by Charles Muurmu 02 Mar '16

02 Mar '16

Dear MariaDB Developers, I am Charles Muurmu and I wish to participate in GSoC 2016 (and 17 if possible) with MariaDB. First, congratulations for passing a successful application with Google. I have gone through the program time line and students applications start in two weeks, However I am interested in two projects for which I will submit 2 proposals. First, I am interested in the Cassandra storage engine V2 as I have basic knowledge on how to write storage engine plugins as well as working knowledge of cassandra. Also I will be having as backup project the GIS enhancement task which requires adding a new geometry type containing the third coordinate, writing importers and exporters for the extended geometry formats... I have two books guiding me for now: Understanding MySQL Internals by O'reilly media and MySQL plugin Development by Sergei Golubchik. While preparing for student application I will be reading mariadb Knowledge base and ask questions on #maria. I will also try to look an the DataStax C++ Driver which will be used. Thanks, Charles.

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[Maria-developers] [GSoC2016] Contribution to Cassandra SE v2
by Olzhas Kaiyrakhmet 02 Mar '16

02 Mar '16

Hello, I am Olzhas Kaiyrakhmet, computer science student at Ulsan National Institute of Science and Technology, Korea. I am interested in contributing to code to MariaDB and participating in GSoC2016. I do find the project, Cassandra SE v2, very interesting for me. Recently, I worked with Cassandra cluster and did look inside of it code. Tried to do some modifications. Also, I have some experience on contributing to distributive systems and databases as research intern in university. I have a great will to contribute for this project with your assistance. Best wishes, Olzhas kaiyrakhmet

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