diff --git a/mysql-test/r/ctype_ucs.result b/mysql-test/r/ctype_ucs.result index 62e2085ae09..dc2bb4c6c73 100644 --- a/mysql-test/r/ctype_ucs.result +++ b/mysql-test/r/ctype_ucs.result @@ -704,6 +704,32 @@ select f1 from t1 where f1 like 'a%'; f1 a drop table t1; +create table t1 (utext varchar(20) character set ucs2); +insert into t1 values ("lily"); +insert into t1 values ("river"); +prepare stmt from 'select utext from t1 where utext like ?'; +set @param1='%%'; +execute stmt using @param1; +utext +lily +river +execute stmt using @param1; +utext +lily +river +select utext from t1 where utext like '%%'; +utext +lily +river +drop table t1; +deallocate prepare stmt; +CREATE TABLE t1 (id int, s char(5) CHARACTER SET ucs2 COLLATE ucs2_unicode_ci); +INSERT INTO t1 VALUES (1, 'ZZZZZ'), (1, 'ZZZ'), (2, 'ZZZ'), (2, 'ZZZZZ'); +SELECT id, MIN(s) FROM t1 GROUP BY id; +id MIN(s) +1 ZZZ +2 ZZZ +DROP TABLE t1; CREATE TABLE t1 (a varchar(64) character set ucs2, b decimal(10,3)); INSERT INTO t1 VALUES ("1.1", 0), ("2.1", 0); update t1 set b=a; diff --git a/mysql-test/r/ctype_utf8.result b/mysql-test/r/ctype_utf8.result index b092a21787f..3dcf88b8df5 100644 --- a/mysql-test/r/ctype_utf8.result +++ b/mysql-test/r/ctype_utf8.result @@ -1152,6 +1152,135 @@ id a 6 bbbbbb 11 bbbbbb DROP TABLE t1; +SET NAMES utf8; +CREATE TABLE t1 ( +a CHAR(13) DEFAULT '', +INDEX(a) +) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci; +INSERT INTO t1 VALUES +('Käli Käli 2-4'), ('Käli Käli 2-4'), +('Käli Käli 2+4'), ('Käli Käli 2+4'), +('Käli Käli 2-6'), ('Käli Käli 2-6'); +INSERT INTO t1 SELECT * FROM t1; +CREATE TABLE t2 ( +a CHAR(13) DEFAULT '', +INDEX(a) +) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci; +INSERT INTO t2 VALUES +('Kali Kali 2-4'), ('Kali Kali 2-4'), +('Kali Kali 2+4'), ('Kali Kali 2+4'), +('Kali Kali 2-6'), ('Kali Kali 2-6'); +INSERT INTO t2 SELECT * FROM t2; +SELECT a FROM t1 WHERE a LIKE 'Käli Käli 2+4'; +a +Käli Käli 2+4 +Käli Käli 2+4 +Käli Käli 2+4 +Käli Käli 2+4 +SELECT a FROM t2 WHERE a LIKE 'Kali Kali 2+4'; +a +Kali Kali 2+4 +Kali Kali 2+4 +Kali Kali 2+4 +Kali Kali 2+4 +EXPLAIN SELECT a FROM t1 WHERE a LIKE 'Käli Käli 2+4'; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 40 NULL 4 Using where; Using index +EXPLAIN SELECT a FROM t1 WHERE a = 'Käli Käli 2+4'; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ref a a 40 const 4 Using where; Using index +EXPLAIN SELECT a FROM t2 WHERE a LIKE 'Kali Kali 2+4'; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 range a a 14 NULL 4 Using where; Using index +EXPLAIN SELECT a FROM t2 WHERE a = 'Kali Kali 2+4'; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ref a a 14 const 4 Using where; Using index +DROP TABLE t1,t2; +CREATE TABLE t1 ( +a char(255) DEFAULT '', +KEY(a(10)) +) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci; +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +a +Käli Käli 2-4 +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +a +Käli Käli 2-4 +Käli Käli 2-4 +DROP TABLE t1; +CREATE TABLE t1 ( +a char(255) DEFAULT '' +) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci; +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +a +Käli Käli 2-4 +Käli Käli 2-4 +ALTER TABLE t1 ADD KEY (a(10)); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +a +Käli Käli 2-4 +Käli Käli 2-4 +DROP TABLE t1; +SET NAMES latin2; +CREATE TABLE t1 ( +id int(11) NOT NULL default '0', +tid int(11) NOT NULL default '0', +val text NOT NULL, +INDEX idx(tid, val(10)) +) ENGINE=MyISAM DEFAULT CHARSET=utf8; +INSERT INTO t1 VALUES +(40988,72,'VOLNÝ ADSL'),(41009,72,'VOLNÝ ADSL'), +(41032,72,'VOLNÝ ADSL'),(41038,72,'VOLNÝ ADSL'), +(41063,72,'VOLNÝ ADSL'),(41537,72,'VOLNÝ ADSL Office'), +(42141,72,'VOLNÝ ADSL'),(42565,72,'VOLNÝ ADSL Combi'), +(42749,72,'VOLNÝ ADSL'),(44205,72,'VOLNÝ ADSL'); +SELECT * FROM t1 WHERE tid=72 and val LIKE 'VOLNY ADSL'; +id tid val +40988 72 VOLNÝ ADSL +41009 72 VOLNÝ ADSL +41032 72 VOLNÝ ADSL +41038 72 VOLNÝ ADSL +41063 72 VOLNÝ ADSL +42141 72 VOLNÝ ADSL +42749 72 VOLNÝ ADSL +44205 72 VOLNÝ ADSL +SELECT * FROM t1 WHERE tid=72 and val LIKE 'VOLNÝ ADSL'; +id tid val +40988 72 VOLNÝ ADSL +41009 72 VOLNÝ ADSL +41032 72 VOLNÝ ADSL +41038 72 VOLNÝ ADSL +41063 72 VOLNÝ ADSL +42141 72 VOLNÝ ADSL +42749 72 VOLNÝ ADSL +44205 72 VOLNÝ ADSL +SELECT * FROM t1 WHERE tid=72 and val LIKE '%VOLNÝ ADSL'; +id tid val +40988 72 VOLNÝ ADSL +41009 72 VOLNÝ ADSL +41032 72 VOLNÝ ADSL +41038 72 VOLNÝ ADSL +41063 72 VOLNÝ ADSL +42141 72 VOLNÝ ADSL +42749 72 VOLNÝ ADSL +44205 72 VOLNÝ ADSL +ALTER TABLE t1 DROP KEY idx; +ALTER TABLE t1 ADD KEY idx (tid,val(11)); +SELECT * FROM t1 WHERE tid=72 and val LIKE 'VOLNÝ ADSL'; +id tid val +40988 72 VOLNÝ ADSL +41009 72 VOLNÝ ADSL +41032 72 VOLNÝ ADSL +41038 72 VOLNÝ ADSL +41063 72 VOLNÝ ADSL +42141 72 VOLNÝ ADSL +42749 72 VOLNÝ ADSL +44205 72 VOLNÝ ADSL +DROP TABLE t1; CREATE TABLE t1(id varchar(20) NOT NULL) DEFAULT CHARSET=utf8; INSERT INTO t1 VALUES ('xxx'), ('aa'), ('yyy'), ('aa'); SELECT id FROM t1; diff --git a/mysql-test/r/distinct.result b/mysql-test/r/distinct.result index 89b17d69f40..a3d1e8bf3bb 100644 --- a/mysql-test/r/distinct.result +++ b/mysql-test/r/distinct.result @@ -504,6 +504,57 @@ a 2 b 2 2 4 3 2 5 DROP TABLE t1,t2; +CREATE TABLE t1(a INT PRIMARY KEY, b INT); +INSERT INTO t1 VALUES (1,1), (2,1), (3,1); +EXPLAIN SELECT DISTINCT a FROM t1; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL PRIMARY 4 NULL 3 Using index +EXPLAIN SELECT DISTINCT a,b FROM t1; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +EXPLAIN SELECT DISTINCT t1_1.a, t1_1.b FROM t1 t1_1, t1 t1_2; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1_1 ALL NULL NULL NULL NULL 3 Using temporary +1 SIMPLE t1_2 index NULL PRIMARY 4 NULL 3 Using index; Distinct +EXPLAIN SELECT DISTINCT t1_1.a, t1_1.b FROM t1 t1_1, t1 t1_2 +WHERE t1_1.a = t1_2.a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1_1 ALL PRIMARY NULL NULL NULL 3 Using temporary +1 SIMPLE t1_2 eq_ref PRIMARY PRIMARY 4 test.t1_1.a 1 Using index; Distinct +EXPLAIN SELECT a FROM t1 GROUP BY a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL PRIMARY 4 NULL 3 Using index +EXPLAIN SELECT a,b FROM t1 GROUP BY a,b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +EXPLAIN SELECT DISTINCT a,b FROM t1 GROUP BY a,b; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ALL NULL NULL NULL NULL 3 +CREATE TABLE t2(a INT, b INT, c INT, d INT, PRIMARY KEY (a,b)); +INSERT INTO t2 VALUES (1,1,1,50), (1,2,3,40), (2,1,3,4); +EXPLAIN SELECT DISTINCT a FROM t2; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 index NULL PRIMARY 8 NULL 3 Using index +EXPLAIN SELECT DISTINCT a,a FROM t2; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 index NULL PRIMARY 8 NULL 3 Using index +EXPLAIN SELECT DISTINCT b,a FROM t2; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 index NULL PRIMARY 8 NULL 3 Using index +EXPLAIN SELECT DISTINCT a,c FROM t2; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using temporary +EXPLAIN SELECT DISTINCT c,a,b FROM t2; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +EXPLAIN SELECT DISTINCT a,b,d FROM t2 GROUP BY c,b,d; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using temporary; Using filesort +CREATE UNIQUE INDEX c_b_unq ON t2 (c,b); +EXPLAIN SELECT DISTINCT a,b,d FROM t2 GROUP BY c,b,d; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t2 ALL NULL NULL NULL NULL 3 +DROP TABLE t1,t2; create table t1 (id int, dsc varchar(50)); insert into t1 values (1, "line number one"), (2, "line number two"), (3, "line number three"); select distinct id, IFNULL(dsc, '-') from t1; diff --git a/mysql-test/t/ctype_ucs.test b/mysql-test/t/ctype_ucs.test index c7662f4f85a..eea0b06b224 100644 --- a/mysql-test/t/ctype_ucs.test +++ b/mysql-test/t/ctype_ucs.test @@ -439,6 +439,32 @@ insert into t1 values('a'); create index t1f1 on t1(f1); select f1 from t1 where f1 like 'a%'; drop table t1; + +# +# Bug#9442 Set parameter make query fail if column character set is UCS2 +# +create table t1 (utext varchar(20) character set ucs2); +insert into t1 values ("lily"); +insert into t1 values ("river"); +prepare stmt from 'select utext from t1 where utext like ?'; +set @param1='%%'; +execute stmt using @param1; +execute stmt using @param1; +select utext from t1 where utext like '%%'; +drop table t1; +deallocate prepare stmt; + +# +# Bug #20076: server crashes for a query with GROUP BY if MIN/MAX aggregation +# over a 'ucs2' field uses a temporary table +# + +CREATE TABLE t1 (id int, s char(5) CHARACTER SET ucs2 COLLATE ucs2_unicode_ci); +INSERT INTO t1 VALUES (1, 'ZZZZZ'), (1, 'ZZZ'), (2, 'ZZZ'), (2, 'ZZZZZ'); + +SELECT id, MIN(s) FROM t1 GROUP BY id; + +DROP TABLE t1; # End of 4.1 tests # diff --git a/mysql-test/t/ctype_utf8.test b/mysql-test/t/ctype_utf8.test index b58a2cf97d4..77b76a14171 100644 --- a/mysql-test/t/ctype_utf8.test +++ b/mysql-test/t/ctype_utf8.test @@ -938,6 +938,94 @@ SELECT id, a FROM t1 WHERE a='bbbbbb' ORDER BY b; DROP TABLE t1; +# +# Bug#16674: LIKE predicate for a utf8 character set column +# + +SET NAMES utf8; + +CREATE TABLE t1 ( + a CHAR(13) DEFAULT '', + INDEX(a) +) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci; +INSERT INTO t1 VALUES + ('Käli Käli 2-4'), ('Käli Käli 2-4'), + ('Käli Käli 2+4'), ('Käli Käli 2+4'), + ('Käli Käli 2-6'), ('Käli Käli 2-6'); +INSERT INTO t1 SELECT * FROM t1; + +CREATE TABLE t2 ( + a CHAR(13) DEFAULT '', + INDEX(a) +) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci; + +INSERT INTO t2 VALUES + ('Kali Kali 2-4'), ('Kali Kali 2-4'), + ('Kali Kali 2+4'), ('Kali Kali 2+4'), + ('Kali Kali 2-6'), ('Kali Kali 2-6'); +INSERT INTO t2 SELECT * FROM t2; + +SELECT a FROM t1 WHERE a LIKE 'Käli Käli 2+4'; +SELECT a FROM t2 WHERE a LIKE 'Kali Kali 2+4'; + +EXPLAIN SELECT a FROM t1 WHERE a LIKE 'Käli Käli 2+4'; +EXPLAIN SELECT a FROM t1 WHERE a = 'Käli Käli 2+4'; +EXPLAIN SELECT a FROM t2 WHERE a LIKE 'Kali Kali 2+4'; +EXPLAIN SELECT a FROM t2 WHERE a = 'Kali Kali 2+4'; + +DROP TABLE t1,t2; + +CREATE TABLE t1 ( + a char(255) DEFAULT '', + KEY(a(10)) +) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci; +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +DROP TABLE t1; + +CREATE TABLE t1 ( + a char(255) DEFAULT '' +) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci; +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +INSERT INTO t1 VALUES ('Käli Käli 2-4'); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +ALTER TABLE t1 ADD KEY (a(10)); +SELECT * FROM t1 WHERE a LIKE 'Käli Käli 2%'; +DROP TABLE t1; + +# +# Bug#18359: LIKE predicate for a 'utf8' text column with a partial index +# (see bug #16674 as well) +# + +SET NAMES latin2; + +CREATE TABLE t1 ( + id int(11) NOT NULL default '0', + tid int(11) NOT NULL default '0', + val text NOT NULL, + INDEX idx(tid, val(10)) +) ENGINE=MyISAM DEFAULT CHARSET=utf8; + +INSERT INTO t1 VALUES + (40988,72,'VOLNÝ ADSL'),(41009,72,'VOLNÝ ADSL'), + (41032,72,'VOLNÝ ADSL'),(41038,72,'VOLNÝ ADSL'), + (41063,72,'VOLNÝ ADSL'),(41537,72,'VOLNÝ ADSL Office'), + (42141,72,'VOLNÝ ADSL'),(42565,72,'VOLNÝ ADSL Combi'), + (42749,72,'VOLNÝ ADSL'),(44205,72,'VOLNÝ ADSL'); + +SELECT * FROM t1 WHERE tid=72 and val LIKE 'VOLNY ADSL'; +SELECT * FROM t1 WHERE tid=72 and val LIKE 'VOLNÝ ADSL'; +SELECT * FROM t1 WHERE tid=72 and val LIKE '%VOLNÝ ADSL'; + +ALTER TABLE t1 DROP KEY idx; +ALTER TABLE t1 ADD KEY idx (tid,val(11)); + +SELECT * FROM t1 WHERE tid=72 and val LIKE 'VOLNÝ ADSL'; + +DROP TABLE t1; # End of 4.1 tests # diff --git a/mysql-test/t/distinct.test b/mysql-test/t/distinct.test index 09f07c2852f..61250a7105e 100644 --- a/mysql-test/t/distinct.test +++ b/mysql-test/t/distinct.test @@ -348,6 +348,34 @@ SELECT DISTINCT a, b, 2 FROM t2; SELECT DISTINCT 2, a, b FROM t2; SELECT DISTINCT a, 2, b FROM t2; +DROP TABLE t1,t2; +# +# Bug#16458: Simple SELECT FOR UPDATE causes "Result Set not updatable" +# error. +# +CREATE TABLE t1(a INT PRIMARY KEY, b INT); +INSERT INTO t1 VALUES (1,1), (2,1), (3,1); +EXPLAIN SELECT DISTINCT a FROM t1; +EXPLAIN SELECT DISTINCT a,b FROM t1; +EXPLAIN SELECT DISTINCT t1_1.a, t1_1.b FROM t1 t1_1, t1 t1_2; +EXPLAIN SELECT DISTINCT t1_1.a, t1_1.b FROM t1 t1_1, t1 t1_2 + WHERE t1_1.a = t1_2.a; +EXPLAIN SELECT a FROM t1 GROUP BY a; +EXPLAIN SELECT a,b FROM t1 GROUP BY a,b; +EXPLAIN SELECT DISTINCT a,b FROM t1 GROUP BY a,b; + +CREATE TABLE t2(a INT, b INT, c INT, d INT, PRIMARY KEY (a,b)); +INSERT INTO t2 VALUES (1,1,1,50), (1,2,3,40), (2,1,3,4); +EXPLAIN SELECT DISTINCT a FROM t2; +EXPLAIN SELECT DISTINCT a,a FROM t2; +EXPLAIN SELECT DISTINCT b,a FROM t2; +EXPLAIN SELECT DISTINCT a,c FROM t2; +EXPLAIN SELECT DISTINCT c,a,b FROM t2; + +EXPLAIN SELECT DISTINCT a,b,d FROM t2 GROUP BY c,b,d; +CREATE UNIQUE INDEX c_b_unq ON t2 (c,b); +EXPLAIN SELECT DISTINCT a,b,d FROM t2 GROUP BY c,b,d; + DROP TABLE t1,t2; # Bug 9784 DISTINCT IFNULL truncates data diff --git a/sql/item_sum.cc b/sql/item_sum.cc index d6bc2c326d6..ea0a3c7d154 100644 --- a/sql/item_sum.cc +++ b/sql/item_sum.cc @@ -2123,7 +2123,6 @@ Item_sum_hybrid::min_max_update_str_field() if (!args[0]->null_value) { - res_str->strip_sp(); result_field->val_str(&tmp_value); if (result_field->is_null() || diff --git a/sql/opt_range.cc b/sql/opt_range.cc index 7aaf9878bae..8da96497985 100644 --- a/sql/opt_range.cc +++ b/sql/opt_range.cc @@ -106,8 +106,8 @@ public: SEL_ARG(Field *field, uint8 part, char *min_value, char *max_value, uint8 min_flag, uint8 max_flag, uint8 maybe_flag); SEL_ARG(enum Type type_arg) - :elements(1),use_count(1),left(0),next_key_part(0),color(BLACK), - type(type_arg),min_flag(0) + :min_flag(0),elements(1),use_count(1),left(0),next_key_part(0), + color(BLACK), type(type_arg) {} inline bool is_same(SEL_ARG *arg) { diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 193a29a1fe9..127409a01bf 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -163,6 +163,10 @@ static Item* part_of_refkey(TABLE *form,Field *field); uint find_shortest_key(TABLE *table, const key_map *usable_keys); static bool test_if_skip_sort_order(JOIN_TAB *tab,ORDER *order, ha_rows select_limit, bool no_changes); +static bool list_contains_unique_index(TABLE *table, + bool (*find_func) (Field *, void *), void *data); +static bool find_field_in_item_list (Field *field, void *data); +static bool find_field_in_order_list (Field *field, void *data); static int create_sort_index(THD *thd, JOIN *join, ORDER *order, ha_rows filesort_limit, ha_rows select_limit); static int remove_duplicates(JOIN *join,TABLE *entry,List &fields, @@ -868,6 +872,40 @@ JOIN::optimize() if (old_group_list && !group_list) select_distinct= 0; } + /* + Check if we can optimize away GROUP BY/DISTINCT. + We can do that if there are no aggregate functions and the + fields in DISTINCT clause (if present) and/or columns in GROUP BY + (if present) contain direct references to all key parts of + an unique index (in whatever order). + Note that the unique keys for DISTINCT and GROUP BY should not + be the same (as long as they are unique). + + The FROM clause must contain a single non-constant table. + */ + if (tables - const_tables == 1 && (group_list || select_distinct) && + !tmp_table_param.sum_func_count && + (!join_tab[const_tables].select || + !join_tab[const_tables].select->quick || + join_tab[const_tables].select->quick->get_type() != + QUICK_SELECT_I::QS_TYPE_GROUP_MIN_MAX)) + { + if (group_list && + list_contains_unique_index(join_tab[const_tables].table, + find_field_in_order_list, + (void *) group_list)) + { + group_list= 0; + group= 0; + } + if (select_distinct && + list_contains_unique_index(join_tab[const_tables].table, + find_field_in_item_list, + (void *) &fields_list)) + { + select_distinct= 0; + } + } if (!group_list && group) { order=0; // The output has only one row @@ -11307,6 +11345,140 @@ test_if_subkey(ORDER *order, TABLE *table, uint ref, uint ref_key_parts, return best; } + +/* + Check if GROUP BY/DISTINCT can be optimized away because the set is + already known to be distinct. + + SYNOPSIS + list_contains_unique_index () + table The table to operate on. + find_func function to iterate over the list and search + for a field + + DESCRIPTION + Used in removing the GROUP BY/DISTINCT of the following types of + statements: + SELECT [DISTINCT] ... FROM + [GROUP BY ,...] + + If (a,b,c is distinct) + then ,{whatever} is also distinct + + This function checks if all the key parts of any of the unique keys + of the table are referenced by a list : either the select list + through find_field_in_item_list or GROUP BY list through + find_field_in_order_list. + If the above holds then we can safely remove the GROUP BY/DISTINCT, + as no result set can be more distinct than an unique key. + + RETURN VALUE + 1 found + 0 not found. +*/ + +static bool +list_contains_unique_index(TABLE *table, + bool (*find_func) (Field *, void *), void *data) +{ + for (uint keynr= 0; keynr < table->s->keys; keynr++) + { + if (keynr == table->s->primary_key || + (table->key_info[keynr].flags & HA_NOSAME)) + { + KEY *keyinfo= table->key_info + keynr; + KEY_PART_INFO *key_part, *key_part_end; + + for (key_part=keyinfo->key_part, + key_part_end=key_part+ keyinfo->key_parts; + key_part < key_part_end; + key_part++) + { + if (!find_func(key_part->field, data)) + break; + } + if (key_part == key_part_end) + return 1; + } + } + return 0; +} + + +/* + Helper function for list_contains_unique_index. + Find a field reference in a list of ORDER structures. + + SYNOPSIS + find_field_in_order_list () + field The field to search for. + data ORDER *.The list to search in + + DESCRIPTION + Finds a direct reference of the Field in the list. + + RETURN VALUE + 1 found + 0 not found. +*/ + +static bool +find_field_in_order_list (Field *field, void *data) +{ + ORDER *group= (ORDER *) data; + bool part_found= 0; + for (ORDER *tmp_group= group; tmp_group; tmp_group=tmp_group->next) + { + Item *item= (*tmp_group->item)->real_item(); + if (item->type() == Item::FIELD_ITEM && + ((Item_field*) item)->field->eq(field)) + { + part_found= 1; + break; + } + } + return part_found; +} + + +/* + Helper function for list_contains_unique_index. + Find a field reference in a dynamic list of Items. + + SYNOPSIS + find_field_in_item_list () + field in The field to search for. + data in List *.The list to search in + + DESCRIPTION + Finds a direct reference of the Field in the list. + + RETURN VALUE + 1 found + 0 not found. +*/ + +static bool +find_field_in_item_list (Field *field, void *data) +{ + List *fields= (List *) data; + bool part_found= 0; + List_iterator li(*fields); + Item *item; + + while ((item= li++)) + { + if (item->type() == Item::FIELD_ITEM && + ((Item_field*) item)->field->eq(field)) + { + part_found= 1; + break; + } + } + return part_found; +} + + /* Test if we can skip the ORDER BY by using an index. diff --git a/strings/ctype-mb.c b/strings/ctype-mb.c index a10dffea66f..898b7a4a57d 100644 --- a/strings/ctype-mb.c +++ b/strings/ctype-mb.c @@ -527,27 +527,20 @@ my_bool my_like_range_mb(CHARSET_INFO *cs, char *min_str,char *max_str, uint *min_length,uint *max_length) { + uint mblen; const char *end= ptr + ptr_length; char *min_org= min_str; char *min_end= min_str + res_length; char *max_end= max_str + res_length; - uint charlen= res_length / cs->mbmaxlen; + uint maxcharlen= res_length / cs->mbmaxlen; - for (; ptr != end && min_str != min_end && charlen > 0 ; ptr++, charlen--) + for (; ptr != end && min_str != min_end && maxcharlen ; maxcharlen--) { + /* We assume here that escape, w_any, w_namy are one-byte characters */ if (*ptr == escape && ptr+1 != end) - { - ptr++; /* Skip escape */ - *min_str++= *max_str++ = *ptr; - continue; - } - if (*ptr == w_one || *ptr == w_many) /* '_' and '%' in SQL */ - { - charlen= my_charpos(cs, min_org, min_str, res_length/cs->mbmaxlen); - - if (charlen < (uint) (min_str - min_org)) - min_str= min_org + charlen; - + ptr++; /* Skip escape */ + else if (*ptr == w_one || *ptr == w_many) /* '_' and '%' in SQL */ + { /* Calculate length of keys: 'a\0\0... is the smallest possible string when we have space expand @@ -571,7 +564,16 @@ my_bool my_like_range_mb(CHARSET_INFO *cs, pad_max_char(cs, max_str, max_end); return 0; } - *min_str++= *max_str++ = *ptr; + if ((mblen= my_ismbchar(cs, ptr, end)) > 1) + { + if (ptr+mblen > end || min_str+mblen > min_end) + break; + while (mblen--) + *min_str++= *max_str++= *ptr++; + } + else + *min_str++= *max_str++= *ptr++; + } *min_length= *max_length = (uint) (min_str - min_org);