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item_cmpfunc.h
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item_cmpfunc.h
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#ifndef ITEM_CMPFUNC_INCLUDED
#define ITEM_CMPFUNC_INCLUDED
/* Copyright (c) 2000, 2015, Oracle and/or its affiliates.
Copyright (c) 2009, 2022, MariaDB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */
/* compare and test functions */
#ifdef USE_PRAGMA_INTERFACE
#pragma interface /* gcc class implementation */
#endif
#include "item_func.h" /* Item_int_func, Item_bool_func */
#include "item.h"
#include "opt_rewrite_date_cmp.h"
extern Item_result item_cmp_type(Item_result a,Item_result b);
inline Item_result item_cmp_type(const Item *a, const Item *b)
{
return item_cmp_type(a->cmp_type(), b->cmp_type());
}
inline Item_result item_cmp_type(Item_result a, const Item *b)
{
return item_cmp_type(a, b->cmp_type());
}
class Item_bool_func2;
class Arg_comparator;
typedef int (Arg_comparator::*arg_cmp_func)();
typedef int (*Item_field_cmpfunc)(Item *f1, Item *f2, void *arg);
class Arg_comparator: public Sql_alloc
{
Item **a, **b;
const Type_handler *m_compare_handler;
CHARSET_INFO *m_compare_collation;
arg_cmp_func func;
Item_func_or_sum *owner;
bool set_null; // TRUE <=> set owner->null_value
Arg_comparator *comparators; // used only for compare_row()
double precision;
/* Fields used in DATE/DATETIME comparison. */
Item *a_cache, *b_cache; // Cached values of a and b items
// when one of arguments is NULL.
int set_cmp_func(THD *thd, Item_func_or_sum *owner_arg,
const Type_handler *compare_handler,
Item **a1, Item **a2);
int compare_not_null_values(longlong val1, longlong val2)
{
if (set_null)
owner->null_value= false;
if (val1 < val2) return -1;
if (val1 == val2) return 0;
return 1;
}
NativeBuffer<STRING_BUFFER_USUAL_SIZE> m_native1, m_native2;
public:
/* Allow owner function to use string buffers. */
String value1, value2;
Arg_comparator():
m_compare_handler(&type_handler_null),
m_compare_collation(&my_charset_bin),
set_null(TRUE), comparators(0),
a_cache(0), b_cache(0) {};
Arg_comparator(Item **a1, Item **a2): a(a1), b(a2),
m_compare_handler(&type_handler_null),
m_compare_collation(&my_charset_bin),
set_null(TRUE), comparators(0),
a_cache(0), b_cache(0) {};
public:
bool set_cmp_func_for_row_arguments(THD *thd);
bool set_cmp_func_row(THD *thd);
bool set_cmp_func_string(THD *thd);
bool set_cmp_func_time(THD *thd);
bool set_cmp_func_datetime(THD *thd);
bool set_cmp_func_native(THD *thd);
bool set_cmp_func_int(THD *thd);
bool set_cmp_func_real(THD *thd);
bool set_cmp_func_decimal(THD *thd);
inline int set_cmp_func(THD *thd, Item_func_or_sum *owner_arg,
const Type_handler *compare_handler,
Item **a1, Item **a2, bool set_null_arg)
{
set_null= set_null_arg;
return set_cmp_func(thd, owner_arg, compare_handler, a1, a2);
}
int set_cmp_func(THD *thd, Item_func_or_sum *owner_arg,
Item **a1, Item **a2, bool set_null_arg)
{
Item *tmp_args[2]= { *a1, *a2 };
Type_handler_hybrid_field_type tmp;
if (tmp.aggregate_for_comparison(owner_arg->func_name_cstring(),
tmp_args, 2, false))
return 1;
return set_cmp_func(thd, owner_arg, tmp.type_handler(),
a1, a2, set_null_arg);
}
inline int compare() { return (this->*func)(); }
int compare_string(); // compare args[0] & args[1]
int compare_real(); // compare args[0] & args[1]
int compare_decimal(); // compare args[0] & args[1]
int compare_int_signed(); // compare args[0] & args[1]
int compare_int_signed_unsigned();
int compare_int_unsigned_signed();
int compare_int_unsigned();
int compare_row(); // compare args[0] & args[1]
int compare_e_string(); // compare args[0] & args[1]
int compare_e_real(); // compare args[0] & args[1]
int compare_e_decimal(); // compare args[0] & args[1]
int compare_e_int(); // compare args[0] & args[1]
int compare_e_int_diff_signedness();
int compare_e_row(); // compare args[0] & args[1]
int compare_real_fixed();
int compare_e_real_fixed();
int compare_datetime();
int compare_e_datetime();
int compare_time();
int compare_e_time();
int compare_native();
int compare_e_native();
int compare_json_str_basic(Item *j, Item *s);
int compare_json_str();
int compare_str_json();
int compare_e_json_str_basic(Item *j, Item *s);
int compare_e_json_str();
int compare_e_str_json();
void min_max_update_field_native(THD *thd, Field *field, Item *item,
int cmp_sign);
Item** cache_converted_constant(THD *thd, Item **value, Item **cache,
const Type_handler *type);
inline bool is_owner_equal_func()
{
return (owner->type() == Item::FUNC_ITEM &&
((Item_func*)owner)->functype() == Item_func::EQUAL_FUNC);
}
const Type_handler *compare_type_handler() const { return m_compare_handler; }
Item_result compare_type() const { return m_compare_handler->cmp_type(); }
CHARSET_INFO *compare_collation() const { return m_compare_collation; }
Arg_comparator *subcomparators() const { return comparators; }
void cleanup()
{
delete [] comparators;
comparators= 0;
}
friend class Item_func;
friend class Item_bool_rowready_func2;
};
class SEL_ARG;
struct KEY_PART;
class Item_bool_func :public Item_int_func,
public Type_cmp_attributes
{
protected:
/*
Build a SEL_TREE for a simple predicate
@param param PARAM from SQL_SELECT::test_quick_select
@param field field in the predicate
@param value constant in the predicate
@return Pointer to the tree built tree
*/
virtual SEL_TREE *get_func_mm_tree(RANGE_OPT_PARAM *param,
Field *field, Item *value)
{
DBUG_ENTER("Item_bool_func::get_func_mm_tree");
DBUG_ASSERT(0);
DBUG_RETURN(0);
}
/*
Return the full select tree for "field_item" and "value":
- a single SEL_TREE if the field is not in a multiple equality, or
- a conjunction of all SEL_TREEs for all fields from
the same multiple equality with "field_item".
*/
SEL_TREE *get_full_func_mm_tree(RANGE_OPT_PARAM *param,
Item_field *field_item, Item *value);
/**
Test if "item" and "value" are suitable for the range optimization
and get their full select tree.
"Suitable" means:
- "item" is a field or a field reference
- "value" is NULL (e.g. WHERE field IS NULL), or
"value" is an unexpensive item (e.g. WHERE field OP value)
@param item - the argument that is checked to be a field
@param value - the other argument
@returns - NULL if the arguments are not suitable for the range optimizer.
@returns - the full select tree if the arguments are suitable.
*/
SEL_TREE *get_full_func_mm_tree_for_args(RANGE_OPT_PARAM *param,
Item *item, Item *value)
{
DBUG_ENTER("Item_bool_func::get_full_func_mm_tree_for_args");
Item *field= item->real_item();
if (field->type() == Item::FIELD_ITEM && !field->const_item() &&
(!value || !value->is_expensive()))
DBUG_RETURN(get_full_func_mm_tree(param, (Item_field *) field, value));
DBUG_RETURN(NULL);
}
SEL_TREE *get_mm_parts(RANGE_OPT_PARAM *param, Field *field,
Item_func::Functype type, Item *value);
SEL_TREE *get_ne_mm_tree(RANGE_OPT_PARAM *param,
Field *field, Item *lt_value, Item *gt_value);
virtual SEL_ARG *get_mm_leaf(RANGE_OPT_PARAM *param, Field *field,
KEY_PART *key_part,
Item_func::Functype type, Item *value);
void raise_note_if_key_become_unused(THD *thd, const Item_args &old_args);
public:
Item_bool_func(THD *thd): Item_int_func(thd) {}
Item_bool_func(THD *thd, Item *a): Item_int_func(thd, a) {}
Item_bool_func(THD *thd, Item *a, Item *b): Item_int_func(thd, a, b) {}
Item_bool_func(THD *thd, Item *a, Item *b, Item *c): Item_int_func(thd, a, b, c) {}
Item_bool_func(THD *thd, List<Item> &list): Item_int_func(thd, list) { }
Item_bool_func(THD *thd, Item_bool_func *item) :Item_int_func(thd, item) {}
const Type_handler *type_handler() const override
{ return &type_handler_bool; }
const Type_handler *fixed_type_handler() const override
{ return &type_handler_bool; }
CHARSET_INFO *compare_collation() const override { return NULL; }
bool fix_length_and_dec(THD *thd) override { decimals=0; max_length=1; return FALSE; }
decimal_digits_t decimal_precision() const override { return 1; }
bool need_parentheses_in_default() override { return true; }
};
/**
Abstract Item class, to represent <code>X IS [NOT] (TRUE | FALSE)</code>
boolean predicates.
*/
class Item_func_truth : public Item_bool_func
{
public:
bool val_bool() override;
longlong val_int() override;
bool fix_length_and_dec(THD *thd) override;
void print(String *str, enum_query_type query_type) override;
enum precedence precedence() const override { return CMP_PRECEDENCE; }
protected:
Item_func_truth(THD *thd, Item *a, bool a_value, bool a_affirmative):
Item_bool_func(thd, a), value(a_value), affirmative(a_affirmative)
{}
~Item_func_truth() = default;
private:
/**
True for <code>X IS [NOT] TRUE</code>,
false for <code>X IS [NOT] FALSE</code> predicates.
*/
const bool value;
/**
True for <code>X IS Y</code>, false for <code>X IS NOT Y</code> predicates.
*/
const bool affirmative;
};
/**
This Item represents a <code>X IS TRUE</code> boolean predicate.
*/
class Item_func_istrue : public Item_func_truth
{
public:
Item_func_istrue(THD *thd, Item *a): Item_func_truth(thd, a, true, true) {}
~Item_func_istrue() = default;
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("istrue") };
return name;
}
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_istrue>(thd, this); }
};
/**
This Item represents a <code>X IS NOT TRUE</code> boolean predicate.
*/
class Item_func_isnottrue : public Item_func_truth
{
public:
Item_func_isnottrue(THD *thd, Item *a):
Item_func_truth(thd, a, true, false) {}
~Item_func_isnottrue() = default;
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("isnottrue") };
return name;
}
bool find_not_null_fields(table_map allowed) override { return false; }
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_isnottrue>(thd, this); }
bool eval_not_null_tables(void *) override
{ not_null_tables_cache= 0; return false; }
};
/**
This Item represents a <code>X IS FALSE</code> boolean predicate.
*/
class Item_func_isfalse : public Item_func_truth
{
public:
Item_func_isfalse(THD *thd, Item *a): Item_func_truth(thd, a, false, true) {}
~Item_func_isfalse() = default;
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("isfalse") };
return name;
}
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_isfalse>(thd, this); }
};
/**
This Item represents a <code>X IS NOT FALSE</code> boolean predicate.
*/
class Item_func_isnotfalse : public Item_func_truth
{
public:
Item_func_isnotfalse(THD *thd, Item *a):
Item_func_truth(thd, a, false, false) {}
~Item_func_isnotfalse() = default;
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("isnotfalse") };
return name;
}
bool find_not_null_fields(table_map allowed) override { return false; }
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_isnotfalse>(thd, this); }
bool eval_not_null_tables(void *) override
{ not_null_tables_cache= 0; return false; }
};
class Item_cache;
#define UNKNOWN (-1)
/*
Item_in_optimizer(left_expr, Item_in_subselect(...))
Item_in_optimizer is used to wrap an instance of Item_in_subselect. This
class does the following:
- Evaluate the left expression and store it in Item_cache_* object (to
avoid re-evaluating it many times during subquery execution)
- Shortcut the evaluation of "NULL IN (...)" to NULL in the cases where we
don't care if the result is NULL or FALSE.
NOTE
It is not quite clear why the above listed functionality should be
placed into a separate class called 'Item_in_optimizer'.
*/
class Item_in_optimizer: public Item_bool_func
{
protected:
Item_cache *cache;
Item *expr_cache;
/*
Stores the value of "NULL IN (SELECT ...)" for uncorrelated subqueries:
UNKNOWN - "NULL in (SELECT ...)" has not yet been evaluated
FALSE - result is FALSE
TRUE - result is NULL
*/
int result_for_null_param;
public:
Item_in_optimizer(THD *thd, Item *a, Item *b):
Item_bool_func(thd, a, b), cache(0), expr_cache(0),
result_for_null_param(UNKNOWN)
{
with_flags|= item_with_t::SUBQUERY;
}
bool fix_fields(THD *, Item **) override;
bool fix_left(THD *thd);
table_map not_null_tables() const override { return 0; }
bool is_null() override;
longlong val_int() override;
void cleanup() override;
enum Functype functype() const override { return IN_OPTIMIZER_FUNC; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<in_optimizer>") };
return name;
}
Item_cache **get_cache() { return &cache; }
Item *transform(THD *thd, Item_transformer transformer, uchar *arg) override;
Item *expr_cache_insert_transformer(THD *thd, uchar *unused) override;
bool is_expensive_processor(void *arg) override;
bool is_expensive() override;
void set_join_tab_idx(uint8 join_tab_idx_arg) override
{ args[1]->set_join_tab_idx(join_tab_idx_arg); }
void get_cache_parameters(List<Item> ¶meters) override;
bool eval_not_null_tables(void *opt_arg) override;
bool find_not_null_fields(table_map allowed) override;
void fix_after_pullout(st_select_lex *new_parent, Item **ref,
bool merge) override;
bool invisible_mode();
bool walk(Item_processor processor, bool walk_subquery, void *arg) override;
void reset_cache() { cache= NULL; }
void print(String *str, enum_query_type query_type) override;
void restore_first_argument();
Item* get_wrapped_in_subselect_item()
{ return args[1]; }
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_in_optimizer>(thd, this); }
enum precedence precedence() const override { return args[1]->precedence(); }
};
/*
Functions and operators with two arguments that can use range optimizer.
*/
class Item_bool_func2 :public Item_bool_func
{ /* Bool with 2 string args */
protected:
void add_key_fields_optimize_op(JOIN *join, KEY_FIELD **key_fields,
uint *and_level, table_map usable_tables,
SARGABLE_PARAM **sargables, bool equal_func);
public:
Item_bool_func2(THD *thd, Item *a, Item *b):
Item_bool_func(thd, a, b) { }
bool is_null() { return MY_TEST(args[0]->is_null() || args[1]->is_null()); }
COND *remove_eq_conds(THD *thd, Item::cond_result *cond_value,
bool top_level);
bool count_sargable_conds(void *arg);
/*
Specifies which result type the function uses to compare its arguments.
This method is used in equal field propagation.
*/
virtual const Type_handler *compare_type_handler() const
{
/*
Have STRING_RESULT by default, which means the function compares
val_str() results of the arguments. This is suitable for Item_func_like
and for Item_func_spatial_rel.
Note, Item_bool_rowready_func2 overrides this default behaviour.
*/
return &type_handler_varchar;
}
SEL_TREE *get_mm_tree(RANGE_OPT_PARAM *param, Item **cond_ptr)
{
DBUG_ENTER("Item_bool_func2::get_mm_tree");
DBUG_ASSERT(arg_count == 2);
SEL_TREE *ftree= get_full_func_mm_tree_for_args(param, args[0], args[1]);
if (!ftree)
ftree= Item_func::get_mm_tree(param, cond_ptr);
DBUG_RETURN(ftree);
}
};
/**
A class for functions and operators that can use the range optimizer and
have a reverse function/operator that can also use the range optimizer,
so this condition:
WHERE value OP field
can be optimized as equivalent to:
WHERE field REV_OP value
This class covers:
- scalar comparison predicates: <, <=, =, <=>, >=, >
- MBR and precise spatial relation predicates (e.g. SP_TOUCHES(x,y))
For example:
WHERE 10 > field
can be optimized as:
WHERE field < 10
*/
class Item_bool_func2_with_rev :public Item_bool_func2
{
protected:
SEL_TREE *get_func_mm_tree(RANGE_OPT_PARAM *param,
Field *field, Item *value)
{
DBUG_ENTER("Item_bool_func2_with_rev::get_func_mm_tree");
Item_func::Functype func_type=
(value != arguments()[0]) ? functype() : rev_functype();
DBUG_RETURN(get_mm_parts(param, field, func_type, value));
}
public:
Item_bool_func2_with_rev(THD *thd, Item *a, Item *b):
Item_bool_func2(thd, a, b) { }
virtual enum Functype rev_functype() const= 0;
SEL_TREE *get_mm_tree(RANGE_OPT_PARAM *param, Item **cond_ptr)
{
DBUG_ENTER("Item_bool_func2_with_rev::get_mm_tree");
DBUG_ASSERT(arg_count == 2);
SEL_TREE *ftree;
/*
Even if get_full_func_mm_tree_for_args(param, args[0], args[1]) will not
return a range predicate it may still be possible to create one
by reversing the order of the operands. Note that this only
applies to predicates where both operands are fields. Example: A
query of the form
WHERE t1.a OP t2.b
In this case, args[0] == t1.a and args[1] == t2.b.
When creating range predicates for t2,
get_full_func_mm_tree_for_args(param, args[0], args[1])
will return NULL because 'field' belongs to t1 and only
predicates that applies to t2 are of interest. In this case a
call to get_full_func_mm_tree_for_args() with reversed operands
may succeed.
*/
if (!(ftree= get_full_func_mm_tree_for_args(param, args[0], args[1])) &&
!(ftree= get_full_func_mm_tree_for_args(param, args[1], args[0])))
ftree= Item_func::get_mm_tree(param, cond_ptr);
DBUG_RETURN(ftree);
}
};
class Item_bool_rowready_func2 :public Item_bool_func2_with_rev
{
protected:
Arg_comparator cmp;
bool check_arguments() const override
{
return check_argument_types_like_args0();
}
public:
Item_bool_rowready_func2(THD *thd, Item *a, Item *b):
Item_bool_func2_with_rev(thd, a, b), cmp(tmp_arg, tmp_arg + 1)
{ }
Sql_mode_dependency value_depends_on_sql_mode() const override;
void print(String *str, enum_query_type query_type) override
{
Item_func::print_op(str, query_type);
}
enum precedence precedence() const override { return CMP_PRECEDENCE; }
Item *neg_transformer(THD *thd) override;
virtual Item *negated_item(THD *thd);
Item *propagate_equal_fields(THD *thd, const Context &ctx, COND_EQUAL *cond)
override
{
Item_args::propagate_equal_fields(thd,
Context(ANY_SUBST,
cmp.compare_type_handler(),
compare_collation()),
cond);
return this;
}
bool fix_length_and_dec(THD *thd) override;
bool fix_length_and_dec_generic(THD *thd,
const Type_handler *compare_handler)
{
DBUG_ASSERT(args == tmp_arg);
return cmp.set_cmp_func(thd, this, compare_handler,
tmp_arg, tmp_arg + 1, true/*set_null*/);
}
int set_cmp_func(THD *thd)
{
DBUG_ASSERT(args == tmp_arg);
return cmp.set_cmp_func(thd, this, tmp_arg, tmp_arg + 1, true/*set_null*/);
}
CHARSET_INFO *compare_collation() const override
{ return cmp.compare_collation(); }
const Type_handler *compare_type_handler() const override
{
return cmp.compare_type_handler();
}
Arg_comparator *get_comparator() { return &cmp; }
void cleanup() override
{
Item_bool_func2::cleanup();
cmp.cleanup();
}
void add_key_fields(JOIN *join, KEY_FIELD **key_fields,
uint *and_level, table_map usable_tables,
SARGABLE_PARAM **sargables) override
{
return add_key_fields_optimize_op(join, key_fields, and_level,
usable_tables, sargables, false);
}
Item *build_clone(THD *thd) override
{
Item_bool_rowready_func2 *clone=
(Item_bool_rowready_func2 *) Item_func::build_clone(thd);
if (clone)
{
clone->cmp.comparators= 0;
}
return clone;
}
};
/**
XOR inherits from Item_bool_func because it is not optimized yet.
Later, when XOR is optimized, it needs to inherit from
Item_cond instead. See WL#5800.
*/
class Item_func_xor :public Item_bool_func
{
public:
Item_func_xor(THD *thd, Item *i1, Item *i2): Item_bool_func(thd, i1, i2) {}
enum Functype functype() const override { return XOR_FUNC; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("xor") };
return name;
}
enum precedence precedence() const override { return XOR_PRECEDENCE; }
void print(String *str, enum_query_type query_type) override
{ Item_func::print_op(str, query_type); }
longlong val_int() override;
bool find_not_null_fields(table_map allowed) override { return false; }
Item *neg_transformer(THD *thd) override;
Item* propagate_equal_fields(THD *thd, const Context &ctx, COND_EQUAL *cond) override
{
Item_args::propagate_equal_fields(thd, Context_boolean(), cond);
return this;
}
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_xor>(thd, this); }
};
class Item_func_not :public Item_bool_func
{
public:
Item_func_not(THD *thd, Item *a): Item_bool_func(thd, a) {}
longlong val_int() override;
enum Functype functype() const override { return NOT_FUNC; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("not") };
return name;
}
bool find_not_null_fields(table_map allowed) override { return false; }
enum precedence precedence() const override { return NEG_PRECEDENCE; }
Item *neg_transformer(THD *thd) override;
bool fix_fields(THD *, Item **) override;
void print(String *str, enum_query_type query_type) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_not>(thd, this); }
};
class Item_maxmin_subselect;
/*
trigcond<param>(arg) ::= param? arg : TRUE
The class Item_func_trig_cond is used for guarded predicates
which are employed only for internal purposes.
A guarded predicate is an object consisting of an a regular or
a guarded predicate P and a pointer to a boolean guard variable g.
A guarded predicate P/g is evaluated to true if the value of the
guard g is false, otherwise it is evaluated to the same value that
the predicate P: val(P/g)= g ? val(P):true.
Guarded predicates allow us to include predicates into a conjunction
conditionally. Currently they are utilized for pushed down predicates
in queries with outer join operations.
In the future, probably, it makes sense to extend this class to
the objects consisting of three elements: a predicate P, a pointer
to a variable g and a firing value s with following evaluation
rule: val(P/g,s)= g==s? val(P) : true. It will allow us to build only
one item for the objects of the form P/g1/g2...
Objects of this class are built only for query execution after
the execution plan has been already selected. That's why this
class needs only val_int out of generic methods.
Current uses of Item_func_trig_cond objects:
- To wrap selection conditions when executing outer joins
- To wrap condition that is pushed down into subquery
*/
class Item_func_trig_cond: public Item_bool_func
{
bool *trig_var;
public:
Item_func_trig_cond(THD *thd, Item *a, bool *f): Item_bool_func(thd, a)
{ trig_var= f; }
longlong val_int() override { return *trig_var ? args[0]->val_int() : 1; }
enum Functype functype() const override { return TRIG_COND_FUNC; };
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("trigcond") };
return name;
}
bool const_item() const override { return FALSE; }
bool *get_trig_var() { return trig_var; }
void add_key_fields(JOIN *join, KEY_FIELD **key_fields,
uint *and_level, table_map usable_tables,
SARGABLE_PARAM **sargables) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_trig_cond>(thd, this); }
};
class Item_func_not_all :public Item_func_not
{
/* allow to check presence of values in max/min optimization */
Item_sum_min_max *test_sum_item;
Item_maxmin_subselect *test_sub_item;
public:
bool show;
Item_func_not_all(THD *thd, Item *a):
Item_func_not(thd, a), test_sum_item(0), test_sub_item(0), show(0)
{}
table_map not_null_tables() const override { return 0; }
longlong val_int() override;
enum Functype functype() const override { return NOT_ALL_FUNC; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<not>") };
return name;
}
enum precedence precedence() const override
{ return show ? Item_func::precedence() : args[0]->precedence(); }
bool fix_fields(THD *thd, Item **ref) override
{ return Item_func::fix_fields(thd, ref);}
void print(String *str, enum_query_type query_type) override;
void set_sum_test(Item_sum_min_max *item) { test_sum_item= item; test_sub_item= 0; };
void set_sub_test(Item_maxmin_subselect *item) { test_sub_item= item; test_sum_item= 0;};
bool empty_underlying_subquery();
Item *neg_transformer(THD *thd) override;
};
class Item_func_nop_all :public Item_func_not_all
{
public:
Item_func_nop_all(THD *thd, Item *a): Item_func_not_all(thd, a) {}
longlong val_int() override;
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<nop>") };
return name;
}
Item *neg_transformer(THD *thd) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_nop_all>(thd, this); }
};
class Item_func_eq :public Item_bool_rowready_func2
{
public:
Item_func_eq(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b),
in_equality_no(UINT_MAX)
{}
longlong val_int() override;
enum Functype functype() const override { return EQ_FUNC; }
enum Functype rev_functype() const override { return EQ_FUNC; }
cond_result eq_cmp_result() const override { return COND_TRUE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("=") };
return name;
}
Item *negated_item(THD *thd) override;
COND *build_equal_items(THD *thd, COND_EQUAL *inherited,
bool link_item_fields,
COND_EQUAL **cond_equal_ref) override;
void add_key_fields(JOIN *join, KEY_FIELD **key_fields,
uint *and_level, table_map usable_tables,
SARGABLE_PARAM **sargables) override
{
return add_key_fields_optimize_op(join, key_fields, and_level,
usable_tables, sargables, true);
}
bool check_equality(THD *thd, COND_EQUAL *cond, List<Item> *eq_list) override;
/*
- If this equality is created from the subquery's IN-equality:
number of the item it was created from, e.g. for
(a,b) IN (SELECT c,d ...) a=c will have in_equality_no=0,
and b=d will have in_equality_no=1.
- Otherwise, UINT_MAX
*/
uint in_equality_no;
uint exists2in_reserved_items() override { return 1; };
friend class Arg_comparator;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_eq>(thd, this); }
Item* date_conds_transformer(THD *thd, uchar *arg) override
{ return do_date_conds_transformation(thd, this); }
Item* varchar_upper_cmp_transformer(THD *thd, uchar *arg) override;
};
class Item_func_equal final :public Item_bool_rowready_func2
{
public:
Item_func_equal(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b) {}
longlong val_int() override;
bool fix_length_and_dec(THD *thd) override;
table_map not_null_tables() const override { return 0; }
bool find_not_null_fields(table_map allowed) override { return false; }
enum Functype functype() const override { return EQUAL_FUNC; }
enum Functype rev_functype() const override { return EQUAL_FUNC; }
cond_result eq_cmp_result() const override { return COND_TRUE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<=>") };
return name;
}
Item *neg_transformer(THD *thd) override { return 0; }
void add_key_fields(JOIN *join, KEY_FIELD **key_fields,
uint *and_level, table_map usable_tables,
SARGABLE_PARAM **sargables) override
{
return add_key_fields_optimize_op(join, key_fields, and_level,
usable_tables, sargables, true);
}
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_equal>(thd, this); }
};
class Item_func_ge :public Item_bool_rowready_func2
{
public:
Item_func_ge(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b) {};
longlong val_int() override;
enum Functype functype() const override { return GE_FUNC; }
enum Functype rev_functype() const override { return LE_FUNC; }
cond_result eq_cmp_result() const override { return COND_TRUE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN(">=") };
return name;
}
Item *negated_item(THD *thd) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_ge>(thd, this); }
Item* date_conds_transformer(THD *thd, uchar *arg) override
{ return do_date_conds_transformation(thd, this); }
};
class Item_func_gt :public Item_bool_rowready_func2
{
public:
Item_func_gt(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b) {};
longlong val_int() override;
enum Functype functype() const override { return GT_FUNC; }
enum Functype rev_functype() const override { return LT_FUNC; }
cond_result eq_cmp_result() const override { return COND_FALSE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN(">") };
return name;
}
Item *negated_item(THD *thd) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_gt>(thd, this); }
Item* date_conds_transformer(THD *thd, uchar *arg) override
{ return do_date_conds_transformation(thd, this); }
};
class Item_func_le :public Item_bool_rowready_func2
{
public:
Item_func_le(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b) {};
longlong val_int() override;
enum Functype functype() const override { return LE_FUNC; }
enum Functype rev_functype() const override { return GE_FUNC; }
cond_result eq_cmp_result() const override { return COND_TRUE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<=") };
return name;
}
Item *negated_item(THD *thd) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_le>(thd, this); }
Item* date_conds_transformer(THD *thd, uchar *arg) override
{ return do_date_conds_transformation(thd, this); }
};
class Item_func_lt :public Item_bool_rowready_func2
{
public:
Item_func_lt(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b) {}
longlong val_int() override;
enum Functype functype() const override { return LT_FUNC; }
enum Functype rev_functype() const override { return GT_FUNC; }
cond_result eq_cmp_result() const override { return COND_FALSE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<") };
return name;
}
Item *negated_item(THD *thd) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_lt>(thd, this); }
Item* date_conds_transformer(THD *thd, uchar *arg) override
{ return do_date_conds_transformation(thd, this); }
};
class Item_func_ne :public Item_bool_rowready_func2
{
protected:
SEL_TREE *get_func_mm_tree(RANGE_OPT_PARAM *param,
Field *field, Item *value) override;
public:
Item_func_ne(THD *thd, Item *a, Item *b):
Item_bool_rowready_func2(thd, a, b) {}
longlong val_int() override;
enum Functype functype() const override { return NE_FUNC; }
enum Functype rev_functype() const override { return NE_FUNC; }
cond_result eq_cmp_result() const override { return COND_FALSE; }
LEX_CSTRING func_name_cstring() const override
{
static LEX_CSTRING name= {STRING_WITH_LEN("<>") };
return name;
}
Item *negated_item(THD *thd) override;
void add_key_fields(JOIN *join, KEY_FIELD **key_fields, uint *and_level,
table_map usable_tables, SARGABLE_PARAM **sargables) override;
Item *get_copy(THD *thd) override
{ return get_item_copy<Item_func_ne>(thd, this); }
};
/*
The class Item_func_opt_neg is defined to factor out the functionality
common for the classes Item_func_between and Item_func_in. The objects
of these classes can express predicates or there negations.
The alternative approach would be to create pairs Item_func_between,
Item_func_notbetween and Item_func_in, Item_func_notin.
*/
class Item_func_opt_neg :public Item_bool_func
{
protected:
/*
The data type handler that will be used for comparison.
Data type handlers of all arguments are mixed to here.
*/
Type_handler_hybrid_field_type m_comparator;
/*
The collation that will be used for comparison in case
when m_compare_type is STRING_RESULT.
*/
DTCollation cmp_collation;
public:
bool negated; /* <=> the item represents NOT <func> */
public:
Item_func_opt_neg(THD *thd, Item *a, Item *b, Item *c):
Item_bool_func(thd, a, b, c), negated(0) {}
Item_func_opt_neg(THD *thd, List<Item> &list):
Item_bool_func(thd, list), negated(0) {}
public:
Item *neg_transformer(THD *thd) override
{
negated= !negated;
return this;
}
bool eq(const Item *item, bool binary_cmp) const override;
CHARSET_INFO *compare_collation() const override
{