Item_func Class Reference

Inheritance diagram for Item_func:

Collaboration diagram for Item_func:

Public Types
enum	Functype {   UNKNOWN_FUNC, EQ_FUNC, EQUAL_FUNC, NE_FUNC,   LT_FUNC, LE_FUNC, GE_FUNC, GT_FUNC,   FT_FUNC, LIKE_FUNC, ISNULL_FUNC, ISNOTNULL_FUNC,   COND_AND_FUNC, COND_OR_FUNC, XOR_FUNC, BETWEEN,   IN_FUNC, MULT_EQUAL_FUNC, INTERVAL_FUNC, ISNOTNULLTEST_FUNC,   SP_EQUALS_FUNC, SP_DISJOINT_FUNC, SP_INTERSECTS_FUNC, 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, NOT_FUNC, NOT_ALL_FUNC,   NOW_FUNC, TRIG_COND_FUNC, SUSERVAR_FUNC, GUSERVAR_FUNC,   COLLATE_FUNC, EXTRACT_FUNC, CHAR_TYPECAST_FUNC, FUNC_SP,   UDF_FUNC, NEG_FUNC, GSYSVAR_FUNC }
enum	optimize_type {   OPTIMIZE_NONE, OPTIMIZE_KEY, OPTIMIZE_OP, OPTIMIZE_NULL,   OPTIMIZE_EQUAL }

Public Member Functions
enum Type	type () const
virtual enum Functype	functype () const
	Item_func (Item *a)
	Item_func (Item *a, Item *b)
	Item_func (Item *a, Item *b, Item *c)
	Item_func (Item *a, Item *b, Item *c, Item *d)
	Item_func (Item *a, Item *b, Item *c, Item *d, Item *e)
	Item_func (List< Item > &list)
	Item_func (THD *thd, Item_func *item)
bool	fix_fields (THD *, Item **ref)
void	fix_after_pullout (st_select_lex *parent_select, st_select_lex *removed_select)
table_map	used_tables () const
virtual table_map	get_initial_pseudo_tables () const
table_map	not_null_tables () const
void	update_used_tables ()
void	set_used_tables (table_map map)
void	set_not_null_tables (table_map map)
bool	eq (const Item *item, bool binary_cmp) const
virtual optimize_type	select_optimize () const
virtual bool	have_rev_func () const
virtual Item *	key_item () const
virtual bool	const_item () const
Item **	arguments () const
void	set_arguments (List< Item > &list)
uint	argument_count () const
void	remove_arguments ()
void	split_sum_func (THD *thd, Ref_ptr_array ref_pointer_array, List< Item > &fields)
virtual void	print (String *str, enum_query_type query_type)
void	print_op (String *str, enum_query_type query_type)
void	print_args (String *str, uint from, enum_query_type query_type)
virtual void	fix_num_length_and_dec ()
void	count_only_length (Item **item, uint nitems)
void	count_real_length ()
void	count_decimal_length ()
void	count_datetime_length (Item **item, uint nitems)
bool	count_string_result_length (enum_field_types field_type, Item **item, uint nitems)
bool	get_arg0_date (MYSQL_TIME *ltime, uint fuzzy_date)
bool	get_arg0_time (MYSQL_TIME *ltime)
bool	is_null ()
void	signal_divide_by_null ()
Field *	tmp_table_field ()
Field *	tmp_table_field (TABLE *t_arg)
Item *	get_tmp_table_item (THD *thd)
my_decimal *	val_decimal (my_decimal *)
bool	agg_arg_charsets (DTCollation &c, Item **items, uint nitems, uint flags, int item_sep)
bool	agg_arg_charsets_for_string_result (DTCollation &c, Item **items, uint nitems, int item_sep=1)
bool	agg_arg_charsets_for_comparison (DTCollation &c, Item **items, uint nitems, int item_sep=1)
bool	agg_arg_charsets_for_string_result_with_comparison (DTCollation &c, Item **items, uint nitems, int item_sep=1)
bool	walk (Item_processor processor, bool walk_subquery, uchar *arg)
Item *	transform (Item_transformer transformer, uchar *arg)
Item *	compile (Item_analyzer analyzer, uchar **arg_p, Item_transformer transformer, uchar *arg_t)
void	traverse_cond (Cond_traverser traverser, void *arg, traverse_order order)
double	fix_result (double value)
void	raise_numeric_overflow (const char *type_name)
double	raise_float_overflow ()
longlong	raise_integer_overflow ()
int	raise_decimal_overflow ()
double	check_float_overflow (double value)
longlong	check_integer_overflow (longlong value, bool val_unsigned)
int	check_decimal_overflow (int error)
bool	has_timestamp_args ()
bool	has_date_args ()
bool	has_time_args ()
bool	has_datetime_args ()
virtual bool	check_valid_arguments_processor (uchar *bool_arg)
virtual bool	find_function_processor (uchar *arg)
Public Member Functions inherited from Item_result_field
	Item_result_field (THD *thd, Item_result_field *item)
Field *	get_tmp_table_field ()
virtual void	fix_length_and_dec ()=0
void	set_result_field (Field *field)
bool	is_result_field ()
void	save_in_result_field (bool no_conversions)
void	cleanup ()
virtual const char *	func_name () const =0
Public Member Functions inherited from Item
	Item (THD *thd, Item *item)
void	rename (char *new_name)
void	init_make_field (Send_field *tmp_field, enum enum_field_types type)
virtual void	make_field (Send_field *field)
virtual Field *	make_string_field (TABLE *table)
void	quick_fix_field ()
type_conversion_status	save_in_field_no_warnings (Field *field, bool no_conversions)
virtual type_conversion_status	save_in_field (Field *field, bool no_conversions)
virtual void	save_org_in_field (Field *field)
virtual type_conversion_status	save_safe_in_field (Field *field)
virtual bool	send (Protocol *protocol, String *str)
virtual Item_result	result_type () const
virtual enum Item_result	numeric_context_result_type () const
enum Item_result	temporal_with_date_as_number_result_type () const
virtual Item_result	cast_to_int_type () const
virtual enum_field_types	string_field_type () const
virtual enum_field_types	field_type () const
virtual enum_monotonicity_info	get_monotonicity_info () const
virtual longlong	val_int_endpoint (bool left_endp, bool *incl_endp)
virtual double	val_real ()=0
virtual longlong	val_int ()=0
virtual longlong	val_date_temporal ()
virtual longlong	val_time_temporal ()
longlong	val_temporal_by_field_type ()
longlong	val_temporal_with_round (enum_field_types type, uint8 dec)
ulonglong	val_uint ()
virtual String *	val_str (String *str)=0
virtual String *	val_str_ascii (String *str)
virtual bool	val_bool ()
virtual String *	val_nodeset (String *)
type_conversion_status	save_time_in_field (Field *field)
type_conversion_status	save_date_in_field (Field *field)
type_conversion_status	save_str_value_in_field (Field *field, String *result)
virtual const char *	full_name () const
virtual double	val_result ()
virtual longlong	val_int_result ()
virtual longlong	val_time_temporal_result ()
virtual longlong	val_date_temporal_result ()
virtual String *	str_result (String *tmp)
virtual my_decimal *	val_decimal_result (my_decimal *val)
virtual bool	val_bool_result ()
virtual bool	is_null_result ()
virtual table_map	resolved_used_tables () const
virtual bool	basic_const_item () const
virtual Item *	clone_item ()
virtual cond_result	eq_cmp_result () const
uint	float_length (uint decimals_par) const
virtual uint	decimal_precision () const
int	decimal_int_part () const
virtual uint	time_precision ()
virtual uint	datetime_precision ()
virtual bool	const_during_execution () const
void	print_item_w_name (String *, enum_query_type query_type)
void	print_for_order (String *str, enum_query_type query_type, bool used_alias)
void	split_sum_func2 (THD *thd, Ref_ptr_array ref_pointer_array, List< Item > &fields, Item **ref, bool skip_registered)
virtual bool	get_date (MYSQL_TIME *ltime, uint fuzzydate)=0
virtual bool	get_time (MYSQL_TIME *ltime)=0
virtual bool	get_timeval (struct timeval *tm, int *warnings)
virtual bool	get_date_result (MYSQL_TIME *ltime, uint fuzzydate)
virtual void	update_null_value ()
virtual void	top_level_item ()
virtual bool	is_bool_func ()
virtual void	no_rows_in_result ()
virtual Item *	copy_or_same (THD *thd)
virtual Item *	copy_andor_structure (THD *thd, bool real_items=false)
virtual Item *	real_item ()
virtual const CHARSET_INFO *	compare_collation ()
virtual const CHARSET_INFO *	charset_for_protocol (void) const
virtual bool	intro_version (uchar *int_arg)
virtual bool	remove_dependence_processor (uchar *arg)
virtual bool	remove_fixed (uchar *arg)
virtual bool	cleanup_processor (uchar *arg)
virtual bool	collect_item_field_processor (uchar *arg)
virtual bool	add_field_to_set_processor (uchar *arg)
virtual bool	remove_column_from_bitmap (uchar *arg)
virtual bool	find_item_in_field_list_processor (uchar *arg)
virtual bool	change_context_processor (uchar *context)
virtual bool	reset_query_id_processor (uchar *query_id_arg)
virtual bool	find_item_processor (uchar *arg)
virtual bool	register_field_in_read_map (uchar *arg)
virtual bool	inform_item_in_cond_of_tab (uchar *join_tab_index)
virtual bool	clean_up_after_removal (uchar *arg)
virtual bool	cache_const_expr_analyzer (uchar **arg)
virtual Item *	cache_const_expr_transformer (uchar *arg)
virtual bool	item_field_by_name_analyzer (uchar **arg)
virtual Item *	item_field_by_name_transformer (uchar *arg)
virtual bool	equality_substitution_analyzer (uchar **arg)
virtual Item *	equality_substitution_transformer (uchar *arg)
virtual bool	check_partition_func_processor (uchar *bool_arg)
virtual bool	subst_argument_checker (uchar **arg)
virtual bool	explain_subquery_checker (uchar **arg)
virtual Item *	explain_subquery_propagator (uchar *arg)
virtual Item *	equal_fields_propagator (uchar *arg)
virtual bool	set_no_const_sub (uchar *arg)
virtual Item *	replace_equal_field (uchar *arg)
virtual Item *	this_item ()
virtual const Item *	this_item () const
virtual Item **	this_item_addr (THD *thd, Item **addr_arg)
virtual uint	cols ()
virtual Item *	element_index (uint i)
virtual Item **	addr (uint i)
virtual bool	check_cols (uint c)
virtual bool	null_inside ()
virtual void	bring_value ()
Field *	tmp_table_field_from_field_type (TABLE *table, bool fixed_length)
virtual Item_field *	field_for_view_update ()
virtual Item *	neg_transformer (THD *thd)
virtual Item *	update_value_transformer (uchar *select_arg)
virtual Item *	safe_charset_converter (const CHARSET_INFO *tocs)
void	delete_self ()
virtual bool	is_splocal ()
virtual Settable_routine_parameter *	get_settable_routine_parameter ()
bool	is_temporal_with_date () const
bool	is_temporal_with_date_and_time () const
bool	is_temporal_with_time () const
bool	is_temporal () const
bool	has_compatible_context (Item *item) const
virtual Field::geometry_type	get_geometry_type () const
String *	check_well_formed_result (String *str, bool send_error=0)
bool	eq_by_collation (Item *item, bool binary_cmp, const CHARSET_INFO *cs)
virtual bool	is_expensive ()
virtual bool	can_be_evaluated_now () const
uint32	max_char_length () const
void	fix_length_and_charset (uint32 max_char_length_arg, const CHARSET_INFO *cs)
void	fix_char_length (uint32 max_char_length_arg)
void	fix_char_length_ulonglong (ulonglong max_char_length_arg)
void	fix_length_and_charset_datetime (uint32 max_char_length_arg)
void	fix_length_and_dec_and_charset_datetime (uint32 max_char_length_arg, uint8 dec_arg)
virtual bool	is_outer_field () const
bool	is_blob_field () const
virtual bool	has_subquery () const
virtual bool	has_stored_program () const
virtual bool	created_by_in2exists () const
	Whether this Item was created by the IN->EXISTS subquery transformation.

Public Attributes
uint	arg_count
Public Attributes inherited from Item_result_field
Field *	result_field
Public Attributes inherited from Item
uint	rsize
String	str_value
Item_name_string	item_name
Item_name_string	orig_name
Item *	next
uint32	max_length
int	marker
uint8	decimals
my_bool	maybe_null
my_bool	null_value
my_bool	unsigned_flag
my_bool	with_sum_func
my_bool	fixed
DTCollation	collation
Item_result	cmp_context

Protected Attributes
Item **	args
Item *	tmp_arg [2]
bool	const_item_cache
	Value used in calculation of result of const_item()
uint	allowed_arg_cols
table_map	used_tables_cache
	Value used in calculation of result of used_tables()
table_map	not_null_tables_cache
	Value used in calculation of result of not_null_tables()

Friends
class	udf_handler

Additional Inherited Members
Static Public Member Functions inherited from Item
static void *	operator new (size_t size) throw ()
static void *	operator new (size_t size, MEM_ROOT *mem_root) throw ()
static void	operator delete (void *ptr, size_t size)
static void	operator delete (void *ptr, MEM_ROOT *mem_root)
static const CHARSET_INFO *	default_charset ()
Protected Member Functions inherited from Item
String *	val_string_from_real (String *str)
String *	val_string_from_int (String *str)
String *	val_string_from_decimal (String *str)
String *	val_string_from_date (String *str)
String *	val_string_from_datetime (String *str)
String *	val_string_from_time (String *str)
my_decimal *	val_decimal_from_real (my_decimal *decimal_value)
my_decimal *	val_decimal_from_int (my_decimal *decimal_value)
my_decimal *	val_decimal_from_string (my_decimal *decimal_value)
my_decimal *	val_decimal_from_date (my_decimal *decimal_value)
my_decimal *	val_decimal_from_time (my_decimal *decimal_value)
longlong	val_int_from_decimal ()
longlong	val_int_from_date ()
longlong	val_int_from_time ()
longlong	val_int_from_datetime ()
double	val_real_from_decimal ()
bool	get_date_from_string (MYSQL_TIME *ltime, uint flags)
bool	get_date_from_real (MYSQL_TIME *ltime, uint flags)
bool	get_date_from_decimal (MYSQL_TIME *ltime, uint flags)
bool	get_date_from_int (MYSQL_TIME *ltime, uint flags)
bool	get_date_from_time (MYSQL_TIME *ltime)
bool	get_date_from_numeric (MYSQL_TIME *ltime, uint fuzzydate)
bool	get_date_from_non_temporal (MYSQL_TIME *ltime, uint fuzzydate)
bool	get_time_from_string (MYSQL_TIME *ltime)
bool	get_time_from_real (MYSQL_TIME *ltime)
bool	get_time_from_decimal (MYSQL_TIME *ltime)
bool	get_time_from_int (MYSQL_TIME *ltime)
bool	get_time_from_date (MYSQL_TIME *ltime)
bool	get_time_from_datetime (MYSQL_TIME *ltime)
bool	get_time_from_numeric (MYSQL_TIME *ltime)
bool	get_time_from_non_temporal (MYSQL_TIME *ltime)

Detailed Description

Definition at line 29 of file item_func.h.

Member Function Documentation

int Item_func::check_decimal_overflow ( int  error )

inline

Throw an error if the error code of a DECIMAL operation is E_DEC_OVERFLOW.

Definition at line 283 of file item_func.h.

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double Item_func::check_float_overflow ( double  value )

inline

Throw an error if the input double number is not finite, i.e. is either +/-INF or NAN.

Definition at line 263 of file item_func.h.

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longlong Item_func::check_integer_overflow ( longlong  value, bool  val_unsigned  )

inline

Throw an error if the input BIGINT value represented by the (longlong value, bool unsigned flag) pair cannot be returned by the function, i.e. is not compatible with this Item's unsigned_flag.

Definition at line 272 of file item_func.h.

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Item * Item_func::compile ( Item_analyzer  analyzer, uchar **  arg_p, Item_transformer  transformer, uchar *  arg_t  )

virtual

Compile Item_func object with a processor and a transformer callback functions.

First the function applies the analyzer to the root node of the Item_func object. Then if the analizer succeeeds (returns TRUE) the function recursively applies the compile method to each argument of the Item_func node. If the call of the method for an argument item returns a new item the old item is substituted for a new one. After this the transformer is applied to the root node of the Item_func object.

Parameters

	analyzer	the analyzer callback function to be applied to the nodes of the tree of the object
[in,out]	arg_p	parameter to be passed to the processor
	transformer	the transformer callback function to be applied to the nodes of the tree of the object
	arg_t	parameter to be passed to the transformer

Returns

Item returned as result of transformation of the node, the same item if no transformation applied, or NULL if transformation caused an error.

Reimplemented from Item.

Reimplemented in Item_cond.

Definition at line 375 of file item_func.cc.

void Item_func::count_datetime_length	(	Item **	item,
		uint	nitems
	)

Count max_length and decimals for temporal functions.

Parameters

item	Argument array
nitems	Number of arguments in the array.

Return values

False

on success, true on error.

Definition at line 599 of file item_func.cc.

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void Item_func::count_decimal_length

(

)

Set max_length/decimals of function if function is fixed point and result length/precision depends on argument ones.

Definition at line 636 of file item_func.cc.

void Item_func::count_only_length	(	Item **	item,
		uint	nitems
	)

Set max_length of if it is maximum length of its arguments.

Definition at line 658 of file item_func.cc.

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void Item_func::count_real_length

(

)

Set max_length/decimals of function if function is floating point and result length/precision depends on argument ones.

Definition at line 676 of file item_func.cc.

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bool Item_func::count_string_result_length	(	enum_field_types	field_type,
		Item **	items,
		uint	nitems
	)

Calculate max_length and decimals for STRING_RESULT functions.

Parameters

field_type	Field type.
items	Argument array.
nitems	Number of arguments.

Return values

False

on success, true on error.

Definition at line 711 of file item_func.cc.

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bool Item_func::eq ( const Item *  item, bool  binary_cmp  ) const

virtual

This function is called when:

• Comparing items in the WHERE clause (when doing where optimization)
• When trying to find an ORDER BY/GROUP BY item in the SELECT part
• When matching fields in multiple equality objects (Item_equal)

Reimplemented from Item.

Reimplemented in Item_func_match, Item_func_get_system_var, Item_extract, Item_date_add_interval, Item_func_date_format, Item_datetime_literal, Item_time_literal, Item_date_literal, Item_func_set_collation, Item_char_typecast, and Item_func_opt_neg.

Definition at line 477 of file item_func.cc.

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virtual bool Item_func::find_function_processor ( uchar *  arg )

inlinevirtual

Find a function of a given type

Parameters

arg	the function type to search (enum Item_func::Functype)

Returns

Return values

TRUE	the function type we're searching for is found
FALSE	the function type wasn't found

This function can be used (together with Item::walk()) to find functions in an item tree fragment.

Reimplemented from Item.

Definition at line 351 of file item_func.h.

void Item_func::fix_after_pullout ( st_select_lex *  parent_select, st_select_lex *  removed_select  )

virtual

Fix after tables have been moved from one select_lex level to the parent level, e.g by semijoin conversion. Basically re-calculate all attributes dependent on the tables.

Parameters

parent_select	select_lex that tables are moved to.
removed_select	select_lex that tables are moved away from, child of parent_select.

Reimplemented from Item.

Reimplemented in Item_cond, and Item_in_optimizer.

Definition at line 239 of file item_func.cc.

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virtual table_map Item_func::get_initial_pseudo_tables ( ) const

inlinevirtual

Returns the pseudo tables depended upon in order to evaluate this function expression. The default implementation returns the empty set.

Reimplemented in Item_func_sp, Item_is_not_null_test, Item_func_sleep, Item_func_sysdate_local, and Item_func_rand.

Definition at line 132 of file item_func.h.

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void Item_func::print ( String *  str, enum_query_type  query_type  )

virtual

This method is used for to:

• to generate a view definition query (SELECT-statement);
• to generate a SQL-query for EXPLAIN EXTENDED;
• to generate a SQL-query to be shown in INFORMATION_SCHEMA;
• debug.

For more information about view definition query, INFORMATION_SCHEMA query and why they should be generated from the Item-tree,

See Also

mysql_register_view().

Reimplemented from Item.

Reimplemented in Item_func_match, Item_func_get_system_var, Item_equal, Item_func_set_user_var, Item_cond, Item_func_regex, Item_func_isnotnull, Item_func_get_format, Item_func_timestamp_diff, Item_func_add_time, Item_func_in, Item_datetime_typecast, Item_time_typecast, Item_date_typecast, Item_func_case, Item_extract, Item_date_add_interval, Item_func_benchmark, Item_func_bit_neg, Item_func_bit, Item_func_locate, Item_datetime_literal, Item_time_literal, Item_func_set_collation, Item_func_nullif, Item_func_conv_charset, Item_date_literal, Item_func_binary, Item_char_typecast, Item_func_strcmp, Item_func_between, Item_func_int_div, Item_func_format, Item_decimal_typecast, Item_func_make_set, Item_func_unsigned, Item_func_not_all, Item_func_signed, Item_func_trig_cond, Item_num_op, Item_func_not, Item_bool_func2, Item_func_trim, and Item_func_truth.

Definition at line 442 of file item_func.cc.

void Item_func::split_sum_func ( THD *  thd, Ref_ptr_array  ref_pointer_array, List< Item > &  fields  )

virtual

See comments in Item_cmp_func::split_sum_func()

Reimplemented from Item.

Reimplemented in Item_cond, and Item_func_make_set.

Definition at line 404 of file item_func.cc.

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Item * Item_func::transform ( Item_transformer  transformer, uchar *  argument  )

virtual

Transform an Item_func object with a transformer callback function.

The function recursively applies the transform method to each argument of the Item_func node. If the call of the method for an argument item returns a new item the old item is substituted for a new one. After this the transformer is applied to the root node of the Item_func object.

Parameters

transformer	the transformer callback function to be applied to the nodes of the tree of the object
argument	parameter to be passed to the transformer

Returns

Item returned as the result of transformation of the root node

Reimplemented from Item.

Reimplemented in Item_equal, Item_cond, Item_func_make_set, and Item_in_optimizer.

Definition at line 323 of file item_func.cc.

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The documentation for this class was generated from the following files:

• sql/item_func.h
• sql/item_func.cc