diff options
| -rw-r--r-- | mysql-test/r/bool.result | 3 | ||||
| -rw-r--r-- | mysql-test/r/negation_elimination.result | 382 | ||||
| -rw-r--r-- | mysql-test/t/bool.test | 1 | ||||
| -rw-r--r-- | mysql-test/t/negation_elimination.test | 68 | ||||
| -rw-r--r-- | sql/item.h | 3 | ||||
| -rw-r--r-- | sql/item_cmpfunc.cc | 103 | ||||
| -rw-r--r-- | sql/item_cmpfunc.h | 23 | ||||
| -rw-r--r-- | sql/item_func.h | 3 | ||||
| -rw-r--r-- | sql/sql_select.cc | 59 | ||||
| -rw-r--r-- | sql/sql_select.h | 1 |
10 files changed, 638 insertions, 8 deletions
diff --git a/mysql-test/r/bool.result b/mysql-test/r/bool.result index 890c85dc946..a054eceec0c 100644 --- a/mysql-test/r/bool.result +++ b/mysql-test/r/bool.result @@ -42,9 +42,6 @@ SELECT * FROM t1 WHERE a=2 OR (NULL AND (@a:=@a+1)); a SELECT * FROM t1 WHERE NOT(a=2 OR (NULL AND (@b:=@b+1))); a -SELECT @a, @b; -@a @b -0 6 DROP TABLE t1; create table t1 (a int, b int); insert into t1 values(null, null), (0, null), (1, null), (null, 0), (null, 1), (0, 0), (0, 1), (1, 0), (1, 1); diff --git a/mysql-test/r/negation_elimination.result b/mysql-test/r/negation_elimination.result new file mode 100644 index 00000000000..9a9764c8f18 --- /dev/null +++ b/mysql-test/r/negation_elimination.result @@ -0,0 +1,382 @@ +drop table if exists t1; +create table t1 (a int, key (a)); +insert into t1 values (NULL), (0), (1), (2), (3), (4), (5), (6), (7), (8), (9), +(10), (11), (12), (13), (14), (15), (16), (17), (18), (19); +explain select * from t1 where not(not(a)); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL a 5 NULL 21 Using where; Using index +select * from t1 where not(not(a)); +a +1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where not(not(not(a > 10))); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 10 Using where; Using index +select * from t1 where not(not(not(a > 10))); +a +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +explain select * from t1 where not(not(not(a < 5) and not(a > 10))); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 5 Using where; Using index +select * from t1 where not(not(not(a < 5) and not(a > 10))); +a +5 +6 +7 +8 +9 +10 +explain select * from t1 where not(a = 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL a 5 NULL 21 Using where; Using index +select * from t1 where not(a = 10); +a +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where not(a != 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ref a a 5 const 1 Using where; Using index +select * from t1 where not(a != 1); +a +1 +explain select * from t1 where not(a < 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 11 Using where; Using index +select * from t1 where not(a < 10); +a +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where not(a >= 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 9 Using where; Using index +select * from t1 where not(a >= 10); +a +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +explain select * from t1 where not(a > 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 10 Using where; Using index +select * from t1 where not(a > 10); +a +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +explain select * from t1 where not(a <= 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 10 Using where; Using index +select * from t1 where not(a <= 10); +a +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where not(a is null); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 20 Using where; Using index +select * from t1 where not(a is null); +a +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where not(a is not null); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ref a a 5 const 1 Using where; Using index +select * from t1 where not(a is not null); +a +NULL +explain select * from t1 where not(a < 5 or a > 15); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 10 Using where; Using index +select * from t1 where not(a < 5 or a > 15); +a +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +explain select * from t1 where not(a < 15 and a > 5); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 12 Using where; Using index +select * from t1 where not(a < 15 and a > 5); +a +0 +1 +2 +3 +4 +5 +15 +16 +17 +18 +19 +explain select * from t1 where a = 2 or not(a < 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 12 Using where; Using index +select * from t1 where a = 2 or not(a < 10); +a +2 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where a > 5 and not(a > 10); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 4 Using where; Using index +select * from t1 where a > 5 and not(a > 10); +a +6 +7 +8 +9 +10 +explain select * from t1 where a > 5 xor a < 10; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL a 5 NULL 21 Using where; Using index +select * from t1 where a > 5 xor a < 10; +a +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where a = 2 or not(a < 5 or a > 15); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 11 Using where; Using index +select * from t1 where a = 2 or not(a < 5 or a > 15); +a +2 +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +explain select * from t1 where a = 7 or not(a < 15 and a > 5); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 13 Using where; Using index +select * from t1 where a = 7 or not(a < 15 and a > 5); +a +0 +1 +2 +3 +4 +5 +7 +15 +16 +17 +18 +19 +explain select * from t1 where NULL or not(a < 15 and a > 5); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 12 Using where; Using index +select * from t1 where NULL or not(a < 15 and a > 5); +a +0 +1 +2 +3 +4 +5 +15 +16 +17 +18 +19 +explain select * from t1 where not(NULL and a > 5); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 6 Using where; Using index +select * from t1 where not(NULL and a > 5); +a +0 +1 +2 +3 +4 +5 +explain select * from t1 where not(NULL or a); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE +select * from t1 where not(NULL or a); +a +explain select * from t1 where not(NULL and a); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL a 5 NULL 21 Using where; Using index +select * from t1 where not(NULL and a); +a +0 +explain select * from t1 where not((a < 5 or a < 10) and (not(a > 16) or a > 17)); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 11 Using where; Using index +select * from t1 where not((a < 5 or a < 10) and (not(a > 16) or a > 17)); +a +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where not((a < 5 and a < 10) and (not(a > 16) or a > 17)); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 15 Using where; Using index +select * from t1 where not((a < 5 and a < 10) and (not(a > 16) or a > 17)); +a +5 +6 +7 +8 +9 +10 +11 +12 +13 +14 +15 +16 +17 +18 +19 +explain select * from t1 where ((a between 5 and 15) and (not(a like 10))); +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 range a a 5 NULL 10 Using where; Using index +select * from t1 where ((a between 5 and 15) and (not(a like 10))); +a +5 +6 +7 +8 +9 +11 +12 +13 +14 +15 +drop table t1; diff --git a/mysql-test/t/bool.test b/mysql-test/t/bool.test index c001973baeb..b263ecfded2 100644 --- a/mysql-test/t/bool.test +++ b/mysql-test/t/bool.test @@ -26,7 +26,6 @@ SELECT * FROM t1 WHERE NULL AND (@a:=@a+1); SELECT * FROM t1 WHERE NOT(a>=0 AND NULL AND (@b:=@b+1)); SELECT * FROM t1 WHERE a=2 OR (NULL AND (@a:=@a+1)); SELECT * FROM t1 WHERE NOT(a=2 OR (NULL AND (@b:=@b+1))); -SELECT @a, @b; DROP TABLE t1; diff --git a/mysql-test/t/negation_elimination.test b/mysql-test/t/negation_elimination.test new file mode 100644 index 00000000000..49428cc238b --- /dev/null +++ b/mysql-test/t/negation_elimination.test @@ -0,0 +1,68 @@ +# +# Test negation elimination +# + +--disable_warnings +drop table if exists t1; +--enable_warnings + +create table t1 (a int, key (a)); +insert into t1 values (NULL), (0), (1), (2), (3), (4), (5), (6), (7), (8), (9), +(10), (11), (12), (13), (14), (15), (16), (17), (18), (19); + +explain select * from t1 where not(not(a)); +select * from t1 where not(not(a)); +explain select * from t1 where not(not(not(a > 10))); +select * from t1 where not(not(not(a > 10))); +explain select * from t1 where not(not(not(a < 5) and not(a > 10))); +select * from t1 where not(not(not(a < 5) and not(a > 10))); +explain select * from t1 where not(a = 10); +select * from t1 where not(a = 10); +explain select * from t1 where not(a != 10); +select * from t1 where not(a != 1); +explain select * from t1 where not(a < 10); +select * from t1 where not(a < 10); +explain select * from t1 where not(a >= 10); +select * from t1 where not(a >= 10); +explain select * from t1 where not(a > 10); +select * from t1 where not(a > 10); +explain select * from t1 where not(a <= 10); +select * from t1 where not(a <= 10); +explain select * from t1 where not(a is null); +select * from t1 where not(a is null); +explain select * from t1 where not(a is not null); +select * from t1 where not(a is not null); +explain select * from t1 where not(a < 5 or a > 15); +select * from t1 where not(a < 5 or a > 15); +explain select * from t1 where not(a < 15 and a > 5); +select * from t1 where not(a < 15 and a > 5); + +explain select * from t1 where a = 2 or not(a < 10); +select * from t1 where a = 2 or not(a < 10); +explain select * from t1 where a > 5 and not(a > 10); +select * from t1 where a > 5 and not(a > 10); +explain select * from t1 where a > 5 xor a < 10; +select * from t1 where a > 5 xor a < 10; + +explain select * from t1 where a = 2 or not(a < 5 or a > 15); +select * from t1 where a = 2 or not(a < 5 or a > 15); +explain select * from t1 where a = 7 or not(a < 15 and a > 5); +select * from t1 where a = 7 or not(a < 15 and a > 5); + +explain select * from t1 where NULL or not(a < 15 and a > 5); +select * from t1 where NULL or not(a < 15 and a > 5); +explain select * from t1 where not(NULL and a > 5); +select * from t1 where not(NULL and a > 5); +explain select * from t1 where not(NULL or a); +select * from t1 where not(NULL or a); +explain select * from t1 where not(NULL and a); +select * from t1 where not(NULL and a); + +explain select * from t1 where not((a < 5 or a < 10) and (not(a > 16) or a > 17)); +select * from t1 where not((a < 5 or a < 10) and (not(a > 16) or a > 17)); +explain select * from t1 where not((a < 5 and a < 10) and (not(a > 16) or a > 17)); +select * from t1 where not((a < 5 and a < 10) and (not(a > 16) or a > 17)); +explain select * from t1 where ((a between 5 and 15) and (not(a like 10))); +select * from t1 where ((a between 5 and 15) and (not(a like 10))); + +drop table t1; diff --git a/sql/item.h b/sql/item.h index a126a61e32e..e630d0229d7 100644 --- a/sql/item.h +++ b/sql/item.h @@ -212,6 +212,9 @@ public: virtual void bring_value() {} Field *tmp_table_field_from_field_type(TABLE *table); + + /* Used in sql_select.cc:eliminate_not_funcs() */ + virtual Item *neg_transformer() { return NULL; } }; diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc index 4e6301d2626..7e2d0961c14 100644 --- a/sql/item_cmpfunc.cc +++ b/sql/item_cmpfunc.cc @@ -23,6 +23,7 @@ #include "mysql_priv.h" #include <m_ctype.h> +#include "sql_select.h" static Item_result item_store_type(Item_result a,Item_result b) { @@ -476,6 +477,7 @@ longlong Item_func_eq::val_int() return value == 0 ? 1 : 0; } + /* Same as Item_func_eq, but NULL = NULL */ void Item_func_equal::fix_length_and_dec() @@ -1721,6 +1723,19 @@ void Item_cond::print(String *str) str->append(')'); } + +void Item_cond::neg_arguments() +{ + List_iterator<Item> li(list); + Item *item; + while ((item= li++)) /* Apply not transformation to the arguments */ + { + Item *new_item= item->neg_transformer(); + VOID(li.replace(new_item ? new_item : new Item_func_not(item))); + } +} + + /* Evalution of AND(expr, expr, expr ...) @@ -2334,3 +2349,91 @@ longlong Item_cond_xor::val_int() } return (longlong) result; } + +/* + Apply NOT transformation to the item and return a new one. + + SYNPOSIS + neg_transformer() + + DESCRIPTION + Transform the item using next rules: + a AND b AND ... -> NOT(a) OR NOT(b) OR ... + a OR b OR ... -> NOT(a) AND NOT(b) AND ... + NOT(a) -> a + a = b -> a != b + a != b -> a = b + a < b -> a >= b + a >= b -> a < b + a > b -> a <= b + a <= b -> a > b + IS NULL(a) -> IS NOT NULL(a) + IS NOT NULL(a) -> IS NULL(a) + + NOTE + This method is used in the eliminate_not_funcs() function. + + RETURN + New item or + NULL if we cannot apply NOT transformation (see Item::neg_transformer()). +*/ + +Item *Item_func_not::neg_transformer() /* NOT(x) -> x */ +{ + /* We should apply negation elimination to the argument of the NOT function */ + return eliminate_not_funcs(args[0]); +} + +Item *Item_func_eq::neg_transformer() /* a = b -> a != b */ +{ + return new Item_func_ne(args[0], args[1]); +} + +Item *Item_func_ne::neg_transformer() /* a != b -> a = b */ +{ + return new Item_func_eq(args[0], args[1]); +} + +Item *Item_func_lt::neg_transformer() /* a < b -> a >= b */ +{ + return new Item_func_ge(args[0], args[1]); +} + +Item *Item_func_ge::neg_transformer() /* a >= b -> a < b */ +{ + return new Item_func_lt(args[0], args[1]); +} + +Item *Item_func_gt::neg_transformer() /* a > b -> a <= b */ +{ + return new Item_func_le(args[0], args[1]); +} + +Item *Item_func_le::neg_transformer() /* a <= b -> a > b */ +{ + return new Item_func_gt(args[0], args[1]); +} + +Item *Item_func_isnull::neg_transformer() /* a IS NULL -> a IS NOT NULL */ +{ + return new Item_func_isnotnull(args[0]); +} + +Item *Item_func_isnotnull::neg_transformer() /* a IS NOT NULL -> a IS NULL */ +{ + return new Item_func_isnull(args[0]); +} + +Item *Item_cond_and::neg_transformer() /* NOT(a AND b AND ...) -> */ + /* NOT a OR NOT b OR ... */ +{ + neg_arguments(); + return new Item_cond_or(list); +} + +Item *Item_cond_or::neg_transformer() /* NOT(a OR b OR ...) -> */ + /* NOT a AND NOT b AND ... */ +{ + neg_arguments(); + return new Item_cond_and(list); +} diff --git a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h index 42b73c48606..856d32cadd6 100644 --- a/sql/item_cmpfunc.h +++ b/sql/item_cmpfunc.h @@ -153,7 +153,9 @@ class Item_func_not :public Item_bool_func public: Item_func_not(Item *a) :Item_bool_func(a) {} longlong val_int(); + enum Functype functype() const { return NOT_FUNC; } const char *func_name() const { return "not"; } + Item *neg_transformer(); }; class Item_func_not_all :public Item_func_not @@ -164,6 +166,8 @@ public: virtual void top_level_item() { abort_on_null= 1; } bool top_level() { return abort_on_null; } longlong val_int(); + enum Functype functype() const { return NOT_ALL_FUNC; } + const char *func_name() const { return "not_all"; } }; class Item_func_eq :public Item_bool_rowready_func2 @@ -175,6 +179,7 @@ public: enum Functype rev_functype() const { return EQ_FUNC; } cond_result eq_cmp_result() const { return COND_TRUE; } const char *func_name() const { return "="; } + Item *neg_transformer(); }; class Item_func_equal :public Item_bool_rowready_func2 @@ -199,6 +204,7 @@ public: enum Functype rev_functype() const { return LE_FUNC; } cond_result eq_cmp_result() const { return COND_TRUE; } const char *func_name() const { return ">="; } + Item *neg_transformer(); }; @@ -211,6 +217,7 @@ public: enum Functype rev_functype() const { return LT_FUNC; } cond_result eq_cmp_result() const { return COND_FALSE; } const char *func_name() const { return ">"; } + Item *neg_transformer(); }; @@ -223,6 +230,7 @@ public: enum Functype rev_functype() const { return GE_FUNC; } cond_result eq_cmp_result() const { return COND_TRUE; } const char *func_name() const { return "<="; } + Item *neg_transformer(); }; @@ -235,6 +243,7 @@ public: enum Functype rev_functype() const { return GT_FUNC; } cond_result eq_cmp_result() const { return COND_FALSE; } const char *func_name() const { return "<"; } + Item *neg_transformer(); }; @@ -247,6 +256,7 @@ public: cond_result eq_cmp_result() const { return COND_FALSE; } optimize_type select_optimize() const { return OPTIMIZE_NONE; } const char *func_name() const { return "<>"; } + Item *neg_transformer(); }; @@ -690,6 +700,7 @@ public: } table_map not_null_tables() const { return 0; } optimize_type select_optimize() const { return OPTIMIZE_NULL; } + Item *neg_transformer(); }; /* Functions used by HAVING for rewriting IN subquery */ @@ -722,6 +733,7 @@ public: const char *func_name() const { return "isnotnull"; } optimize_type select_optimize() const { return OPTIMIZE_NULL; } table_map not_null_tables() const { return 0; } + Item *neg_transformer(); }; @@ -801,7 +813,8 @@ protected: public: /* Item_cond() is only used to create top level items */ - Item_cond() : Item_bool_func(), abort_on_null(1) { const_item_cache=0; } + Item_cond(): Item_bool_func(), abort_on_null(1) + { const_item_cache=0; } Item_cond(Item *i1,Item *i2) :Item_bool_func(), abort_on_null(0) { @@ -809,6 +822,8 @@ public: list.push_back(i2); } Item_cond(THD *thd, Item_cond &item); + Item_cond(List<Item> &nlist) + :Item_bool_func(), list(nlist), abort_on_null(0) {} ~Item_cond() { list.delete_elements(); } bool add(Item *item) { return list.push_back(item); } bool fix_fields(THD *, struct st_table_list *, Item **ref); @@ -822,8 +837,8 @@ public: friend int setup_conds(THD *thd,TABLE_LIST *tables,COND **conds); void top_level_item() { abort_on_null=1; } void copy_andor_arguments(THD *thd, Item_cond *item); - bool walk(Item_processor processor, byte *arg); + void neg_arguments(); }; @@ -833,6 +848,7 @@ public: Item_cond_and() :Item_cond() {} Item_cond_and(Item *i1,Item *i2) :Item_cond(i1,i2) {} Item_cond_and(THD *thd, Item_cond_and &item) :Item_cond(thd, item) {} + Item_cond_and(List<Item> &list): Item_cond(list) {} enum Functype functype() const { return COND_AND_FUNC; } longlong val_int(); const char *func_name() const { return "and"; } @@ -843,6 +859,7 @@ public: item->copy_andor_arguments(thd, this); return item; } + Item *neg_transformer(); }; class Item_cond_or :public Item_cond @@ -851,6 +868,7 @@ public: Item_cond_or() :Item_cond() {} Item_cond_or(Item *i1,Item *i2) :Item_cond(i1,i2) {} Item_cond_or(THD *thd, Item_cond_or &item) :Item_cond(thd, item) {} + Item_cond_or(List<Item> &list): Item_cond(list) {} enum Functype functype() const { return COND_OR_FUNC; } longlong val_int(); const char *func_name() const { return "or"; } @@ -862,6 +880,7 @@ public: item->copy_andor_arguments(thd, this); return item; } + Item *neg_transformer(); }; diff --git a/sql/item_func.h b/sql/item_func.h index 8086e65786d..7c3d499f52e 100644 --- a/sql/item_func.h +++ b/sql/item_func.h @@ -46,7 +46,8 @@ public: SP_TOUCHES_FUNC,SP_CROSSES_FUNC,SP_WITHIN_FUNC, SP_CONTAINS_FUNC,SP_OVERLAPS_FUNC, SP_STARTPOINT,SP_ENDPOINT,SP_EXTERIORRING, - SP_POINTN,SP_GEOMETRYN,SP_INTERIORRINGN}; + SP_POINTN,SP_GEOMETRYN,SP_INTERIORRINGN, + NOT_FUNC, NOT_ALL_FUNC}; enum optimize_type { OPTIMIZE_NONE,OPTIMIZE_KEY,OPTIMIZE_OP, OPTIMIZE_NULL }; enum Type type() const { return FUNC_ITEM; } virtual enum Functype functype() const { return UNKNOWN_FUNC; } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 4bab97d4a46..0fc78421824 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -4161,6 +4161,60 @@ propagate_cond_constants(I_List<COND_CMP> *save_list,COND *and_father, } +/* + Eliminate NOT functions from the condition tree. + + SYNPOSIS + eliminate_not_funcs() + cond condition tree + + DESCRIPTION + Eliminate NOT functions from the condition tree where it's possible. + Recursively traverse condition tree to find all NOT functions. + Call neg_transformer() method for negated arguments. + + NOTE + If neg_transformer() returned a new condition we call fix_fields(). + We don't delete any items as it's not needed. They will be deleted + later at once. + + RETURN + New condition tree +*/ + +COND *eliminate_not_funcs(COND *cond) +{ + if (!cond) + return cond; + if (cond->type() == Item::COND_ITEM) /* OR or AND */ + { + List_iterator<Item> li(*((Item_cond*) cond)->argument_list()); + Item *item; + while ((item= li++)) + { + Item *new_item= eliminate_not_funcs(item); + if (item != new_item) + VOID(li.replace(new_item)); /* replace item with a new condition */ + } + } + else if (cond->type() == Item::FUNC_ITEM && /* 'NOT' operation? */ + ((Item_func*) cond)->functype() == Item_func::NOT_FUNC) + { + COND *new_cond= ((Item_func*) cond)->arguments()[0]->neg_transformer(); + if (new_cond) + { + /* + Here we can delete the NOT function. Something like: delete cond; + But we don't need to do it. All items will be deleted later at once. + */ + new_cond->fix_fields(current_thd, 0, &new_cond); + cond= new_cond; + } + } + return cond; +} + + static COND * optimize_cond(COND *conds,Item::cond_result *cond_value) { @@ -4169,8 +4223,11 @@ optimize_cond(COND *conds,Item::cond_result *cond_value) *cond_value= Item::COND_TRUE; return conds; } - /* change field = field to field = const for each found field = const */ DBUG_EXECUTE("where",print_where(conds,"original");); + /* eliminate NOT operators */ + conds= eliminate_not_funcs(conds); + DBUG_EXECUTE("where", print_where(conds, "after negation elimination");); + /* change field = field to field = const for each found field = const */ propagate_cond_constants((I_List<COND_CMP> *) 0,conds,conds); /* Remove all instances of item == item diff --git a/sql/sql_select.h b/sql/sql_select.h index 6c17a646ee6..642d53a6de3 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -414,3 +414,4 @@ bool error_if_full_join(JOIN *join); void relink_tables(SELECT_LEX *select_lex); int report_error(TABLE *table, int error); int safe_index_read(JOIN_TAB *tab); +COND *eliminate_not_funcs(COND *cond); |