Item_func_pi Class Reference

#include <item.h>

Inheritance diagram for Item_func_pi:

Public Member Functions
	Item_func_pi (const POS &pos)
void	print (const THD *, String *str, enum_query_type) const override
	This method is used for to: More...
Item *	safe_charset_converter (THD *thd, const CHARSET_INFO *tocs) override
Public Member Functions inherited from Item_float
	Item_float (const char *str_arg, uint length)
	Item_float (const POS &pos, const char *str_arg, uint length)
	Item_float (const Name_string name_arg, double val_arg, uint decimal_par, uint length)
	Item_float (const POS &pos, const Name_string name_arg, double val_arg, uint decimal_par, uint length)
	Item_float (double value_par, uint decimal_par)
enum Type	type () const override
double	val_real () override
longlong	val_int () override
String *	val_str (String *) override
my_decimal *	val_decimal (my_decimal *) override
bool	get_date (MYSQL_TIME *ltime, my_time_flags_t fuzzydate) override
bool	get_time (MYSQL_TIME *ltime) override
Item *	clone_item () const override
Item_num *	neg () override
bool	eq (const Item *, bool binary_cmp) const override
Public Member Functions inherited from Item_num
	Item_num ()
	Item_num (const POS &pos)
bool	check_partition_func_processor (uchar *) override
	Check if a partition function is allowed. More...
Public Member Functions inherited from Item_basic_constant
	Item_basic_constant ()
	Item_basic_constant (const POS &pos)
void	set_used_tables (table_map map)
table_map	used_tables () const override
bool	check_function_as_value_generator (uchar *) override
	Check if this item is allowed for a virtual column or inside a default expression. More...
void	cleanup () override
	Called for every Item after use (preparation and execution). More...
bool	basic_const_item () const override
	Returns true if this is a simple constant item like an integer, not a constant expression. More...
void	set_str_value (String *str)
Public Member Functions inherited from Item
	Item (const Item &)=delete
void	operator= (Item &)=delete
	Item ()
	Item constructor for general use. More...
	Item (THD *thd, const Item *item)
	Constructor used by Item_field, Item_ref & aggregate functions. More...
	Item (const POS &)
	Parse-time context-independent constructor. More...
	~Item () override=default
virtual bool	itemize (Parse_context *pc, Item **res)
	The same as contextualize() but with additional parameter. More...
void	rename (char *new_name)
	rename item (used for views, cleanup() return original name). More...
void	init_make_field (Send_field *tmp_field, enum enum_field_types type)
virtual void	notify_removal ()
	Called when an item has been removed, can be used to notify external objects about the removal, e.g subquery predicates that are part of the sj_candidates container. More...
virtual void	make_field (Send_field *field)
virtual Field *	make_string_field (TABLE *table) const
	Create a field to hold a string value from an item. More...
virtual bool	fix_fields (THD *, Item **)
virtual void	fix_after_pullout (Query_block *parent_query_block, Query_block *removed_query_block)
	Fix after tables have been moved from one query_block level to the parent level, e.g by semijoin conversion. More...
void	quick_fix_field ()
virtual void	set_can_use_prefix_key ()
virtual bool	propagate_type (THD *thd, const Type_properties &type)
	Propagate data type specifications into parameters and user variables. More...
bool	propagate_type (THD *thd, enum_field_types def=MYSQL_TYPE_VARCHAR, bool pin=false, bool inherit=false)
	Wrapper for easier calling of propagate_type(const Type_properties &). More...
virtual void	mark_json_as_scalar ()
	For Items with data type JSON, mark that a string argument is treated as a scalar JSON value. More...
virtual std::optional< ContainedSubquery >	get_contained_subquery (const Query_block *outer_query_block)
	If this item represents a IN/ALL/ANY/comparison_operator subquery, return that (along with data on how it will be executed). More...
type_conversion_status	save_in_field_no_warnings (Field *field, bool no_conversions)
	Save the item into a field but do not emit any warnings. More...
type_conversion_status	save_in_field (Field *field, bool no_conversions)
	Save a temporal value in packed longlong format into a Field. More...
void	save_in_field_no_error_check (Field *field, bool no_conversions)
	A slightly faster value of save_in_field() that returns no error value (you will need to check thd->is_error() yourself), and does not support saving into hidden fields for functional indexes. More...
virtual void	save_org_in_field (Field *field)
virtual bool	send (Protocol *protocol, String *str)
	This is only called from items that is not of type item_field. More...
bool	evaluate (THD *thd, String *str)
	Evaluate item, possibly using the supplied buffer. More...
virtual Item_result	result_type () const
virtual Item_result	numeric_context_result_type () const
	Result type when an item appear in a numeric context. More...
Item_result	temporal_with_date_as_number_result_type () const
	Similar to result_type() but makes DATE, DATETIME, TIMESTAMP pretend to be numbers rather than strings. More...
virtual void	set_data_type_inherited ()
	Set data type for item as inherited. More...
virtual void	pin_data_type ()
	Pin the data type for the item. More...
enum_field_types	data_type () const
	Retrieve the derived data type of the Item. More...
virtual enum_field_types	actual_data_type () const
	Retrieve actual data type for an item. More...
virtual enum_field_types	default_data_type () const
	Get the default data (output) type for the specific item. More...
void	set_data_type (enum_field_types data_type)
	Set the data type of the current Item. More...
void	set_data_type_null ()
void	set_data_type_bool ()
void	set_data_type_longlong ()
	Set the data type of the Item to be longlong. More...
void	set_data_type_decimal (uint8 precision, uint8 scale)
	Set the data type of the Item to be decimal. More...
void	set_data_type_double ()
	Set the data type of the Item to be double precision floating point. More...
void	set_data_type_float ()
	Set the data type of the Item to be single precision floating point. More...
void	set_data_type_string (uint32 max_l)
	Set the Item to be variable length string. More...
void	set_data_type_string (ulonglong max_char_length_arg)
	Set the Item to be variable length string. More...
void	set_data_type_string (uint32 max_l, const CHARSET_INFO *cs)
	Set the Item to be variable length string. More...
void	set_data_type_string (uint32 max_l, const DTCollation &coll)
	Set the Item to be variable length string. More...
void	set_data_type_char (uint32 max_l)
	Set the Item to be fixed length string. More...
void	set_data_type_char (uint32 max_l, const CHARSET_INFO *cs)
	Set the Item to be fixed length string. More...
void	set_data_type_blob (uint32 max_l)
	Set the Item to be of BLOB type. More...
void	set_data_type_date ()
	Set all type properties for Item of DATE type. More...
void	set_data_type_time (uint8 fsp)
	Set all type properties for Item of TIME type. More...
void	set_data_type_datetime (uint8 fsp)
	Set all properties for Item of DATETIME type. More...
void	set_data_type_timestamp (uint8 fsp)
	Set all properties for Item of TIMESTAMP type. More...
void	set_data_type_geometry ()
	Set the data type of the Item to be GEOMETRY. More...
void	set_data_type_json ()
	Set the data type of the Item to be JSON. More...
void	set_data_type_year ()
	Set the data type of the Item to be YEAR. More...
void	set_data_type_bit ()
	Set the data type of the Item to be bit. More...
void	set_data_type_from_item (const Item *item)
	Set data type properties of the item from the properties of another item. More...
virtual TYPELIB *	get_typelib () const
	Get the typelib information for an item of type set or enum. More...
virtual Item_result	cast_to_int_type () const
void	aggregate_type (Bounds_checked_array< Item * > items)
	Aggregates data types from array of items into current item. More...
virtual enum_monotonicity_info	get_monotonicity_info () const
virtual longlong	val_int_endpoint (bool left_endp, bool *incl_endp)
virtual longlong	val_date_temporal ()
	Return date value of item in packed longlong format. More...
virtual longlong	val_time_temporal ()
	Return time value of item in packed longlong format. More...
longlong	val_temporal_by_field_type ()
	Return date or time value of item in packed longlong format, depending on item field type. More...
longlong	int_sort_key ()
	Produces a key suitable for filesort. More...
longlong	val_temporal_with_round (enum_field_types type, uint8 dec)
	Get date or time value in packed longlong format. More...
ulonglong	val_uint ()
virtual String *	val_str_ascii (String *str)
virtual bool	val_bool ()
virtual bool	val_json (Json_wrapper *result)
	Get a JSON value from an Item. More...
virtual float	get_filtering_effect (THD *thd, table_map filter_for_table, table_map read_tables, const MY_BITMAP *fields_to_ignore, double rows_in_table)
	Calculate the filter contribution that is relevant for table 'filter_for_table' for this item. More...
bool	error_json ()
	Get the value to return from val_json() in case of errors. More...
bool	get_date_from_non_temporal (MYSQL_TIME *ltime, my_time_flags_t fuzzydate)
	Convert a non-temporal type to date. More...
bool	get_time_from_non_temporal (MYSQL_TIME *ltime)
	Convert a non-temporal type to time. More...
my_decimal *	error_decimal (my_decimal *decimal_value)
	Get the value to return from val_decimal() in case of errors. More...
String *	error_str ()
	Get the value to return from val_str() in case of errors. More...
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 Field *	get_tmp_table_field ()
	If this Item is being materialized into a temporary table, returns the field that is being materialized into. More...
virtual Field *	tmp_table_field (TABLE *)
virtual const char *	full_name () const
virtual table_map	not_null_tables () const
	Return table map of tables that can't be NULL tables (tables that are used in a context where if they would contain a NULL row generated by a LEFT or RIGHT join, the item would not be true). More...
bool	may_eval_const_item (const THD *thd) const
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 ()
	TIME precision of the item: 0..6. More...
virtual uint	datetime_precision ()
	DATETIME precision of the item: 0..6. More...
bool	const_item () const
	Returns true if item is constant, regardless of query evaluation state. More...
bool	const_for_execution () const
	Returns true if item is constant during one query execution. More...
bool	may_evaluate_const (const THD *thd) const
	Return true if this is a const item that may be evaluated in the current phase of statement processing. More...
bool	is_non_deterministic () const
bool	is_outer_reference () const
void	print_item_w_name (const THD *thd, String *, enum_query_type query_type) const
void	print_for_order (const THD *thd, String *str, enum_query_type query_type, bool used_alias) const
	Prints the item when it's part of ORDER BY and GROUP BY. More...
virtual void	update_used_tables ()
	Updates used tables, not null tables information and accumulates properties up the item tree, cf. More...
virtual void	split_sum_func (THD *, Ref_item_array, mem_root_deque< Item * > *)
void	split_sum_func2 (THD *thd, Ref_item_array ref_item_array, mem_root_deque< Item * > *fields, Item **ref, bool skip_registered)
virtual bool	get_timeval (my_timeval *tm, int *warnings)
	Get timestamp in "struct timeval" format. More...
virtual bool	is_null ()
	The method allows to determine nullness of a complex expression without fully evaluating it, instead of calling val*() then checking null_value. More...
bool	update_null_value ()
	Make sure the null_value member has a correct value. More...
virtual void	apply_is_true ()
	Apply the IS TRUE truth property, meaning that an UNKNOWN result and a FALSE result are treated the same. More...
virtual void	set_result_field (Field *)
virtual bool	is_result_field () const
virtual Field *	get_result_field () const
virtual bool	is_bool_func () const
virtual void	no_rows_in_result ()
virtual Item *	copy_or_same (THD *)
virtual Item *	copy_andor_structure (THD *)
virtual Item *	real_item ()
virtual const Item *	real_item () const
virtual Item *	get_tmp_table_item (THD *thd)
	If an Item is materialized in a temporary table, a different Item may have to be used in the part of the query that runs after the materialization. More...
virtual const CHARSET_INFO *	compare_collation () const
virtual const CHARSET_INFO *	charset_for_protocol ()
virtual bool	walk (Item_processor processor, enum_walk walk, uchar *arg)
	Traverses a tree of Items in prefix and/or postfix order. More...
template<class T >
auto	walk_helper_thunk (uchar *arg)
template<class T >
auto	analyze_helper_thunk (uchar **arg)
	See CompileItem. More...
virtual Item *	transform (Item_transformer transformer, uchar *arg)
	Perform a generic transformation of the Item tree, by adding zero or more additional Item objects to it. More...
virtual Item *	compile (Item_analyzer analyzer, uchar **arg_p, Item_transformer transformer, uchar *arg_t)
	Perform a generic "compilation" of the Item tree, ie transform the Item tree by adding zero or more Item objects to it. More...
virtual void	traverse_cond (Cond_traverser traverser, void *arg, traverse_order)
virtual bool	intro_version (uchar *)
bool	cleanup_processor (uchar *)
	cleanup() item if it is resolved ('fixed'). More...
virtual bool	collect_item_field_processor (uchar *)
virtual bool	collect_item_field_or_ref_processor (uchar *)
virtual bool	collect_item_field_or_view_ref_processor (uchar *)
	Collects fields and view references that have the qualifying table in the specified query block. More...
virtual bool	add_field_to_set_processor (uchar *)
	Item::walk function. More...
virtual bool	visitor_processor (uchar *arg)
	A processor to handle the select lex visitor framework. More...
virtual bool	add_field_to_cond_set_processor (uchar *)
	Item::walk function. More...
virtual bool	remove_column_from_bitmap (uchar *arg)
	Visitor interface for removing all column expressions (Item_field) in this expression tree from a bitmap. More...
virtual bool	find_item_in_field_list_processor (uchar *)
virtual bool	change_context_processor (uchar *)
virtual bool	find_item_processor (uchar *arg)
virtual bool	is_non_const_over_literals (uchar *)
virtual bool	find_field_processor (uchar *)
	Is this an Item_field which references the given Field argument? More...
virtual bool	cast_incompatible_args (uchar *)
	Wrap incompatible arguments in CAST nodes to the expected data types. More...
virtual bool	mark_field_in_map (uchar *arg)
	Mark underlying field in read or write map of a table. More...
virtual bool	reset_wf_state (uchar *arg)
	Reset execution state for such window function types as determined by arg. More...
virtual bool	used_tables_for_level (uchar *arg)
	Return used table information for the specified query block (level). More...
virtual bool	check_column_privileges (uchar *thd)
	Check privileges. More...
virtual bool	inform_item_in_cond_of_tab (uchar *)
virtual void	bind_fields ()
	Bind objects from the current execution context to field objects in item trees. More...
virtual bool	clean_up_after_removal (uchar *arg)
	Clean up after removing the item from the item tree. More...
virtual bool	aggregate_check_distinct (uchar *)
virtual bool	aggregate_check_group (uchar *)
virtual bool	is_strong_side_column_not_in_fd (uchar *)
virtual bool	is_column_not_in_fd (uchar *)
virtual Bool3	local_column (const Query_block *) const
virtual bool	collect_scalar_subqueries (uchar *)
virtual bool	collect_grouped_aggregates (uchar *)
virtual bool	collect_subqueries (uchar *)
virtual bool	update_depended_from (uchar *)
virtual bool	has_aggregate_ref_in_group_by (uchar *)
	Check if an aggregate is referenced from within the GROUP BY clause of the query block in which it is aggregated. More...
bool	visit_all_analyzer (uchar **)
virtual bool	cache_const_expr_analyzer (uchar **cache_item)
	Check if an item is a constant one and can be cached. More...
Item *	cache_const_expr_transformer (uchar *item)
	Cache item if needed. More...
virtual bool	equality_substitution_analyzer (uchar **)
virtual Item *	equality_substitution_transformer (uchar *)
virtual bool	subst_argument_checker (uchar **arg)
virtual bool	explain_subquery_checker (uchar **)
virtual Item *	explain_subquery_propagator (uchar *)
virtual Item *	equal_fields_propagator (uchar *)
virtual bool	disable_constant_propagation (uchar *)
virtual Item *	replace_equal_field (uchar *)
virtual bool	check_valid_arguments_processor (uchar *)
virtual bool	check_gcol_depend_default_processor (uchar *args)
	Check if a generated expression depends on DEFAULT function with specific column name as argument. More...
virtual bool	is_valid_for_pushdown (uchar *arg)
	Check if all the columns present in this expression are from the derived table. More...
virtual bool	check_column_in_window_functions (uchar *arg)
	Check if all the columns present in this expression are present in PARTITION clause of window functions of the derived table. More...
virtual bool	check_column_in_group_by (uchar *arg)
	Check if all the columns present in this expression are present in GROUP BY clause of the derived table. More...
virtual Item *	replace_with_derived_expr (uchar *arg)
	Assuming this expression is part of a condition that would be pushed to the WHERE clause of a materialized derived table, replace, in this expression, each derived table's column with a clone of the expression lying under it in the derived table's definition. More...
virtual Item *	replace_with_derived_expr_ref (uchar *arg)
	Assuming this expression is part of a condition that would be pushed to the HAVING clause of a materialized derived table, replace, in this expression, each derived table's column with a reference to the expression lying under it in the derived table's definition. More...
virtual Item *	replace_view_refs_with_clone (uchar *arg)
	Assuming this expression is part of a condition that would be pushed to a materialized derived table, replace, in this expression, each view reference with a clone of the expression in merged derived table's definition. More...
virtual Item *	this_item ()
virtual const Item *	this_item () const
virtual Item **	this_item_addr (THD *, Item **addr_arg)
virtual uint	cols () const
virtual Item *	element_index (uint)
virtual Item **	addr (uint)
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) const
	Create a field based on field_type of argument. More...
virtual Item_field *	field_for_view_update ()
virtual Item *	truth_transformer (THD *thd, Bool_test test)
	Informs an item that it is wrapped in a truth test, in case it wants to transforms itself to implement this test by itself. More...
virtual Item *	update_value_transformer (uchar *)
virtual Item *	replace_scalar_subquery (uchar *)
	When walking the item tree seeing an Item_singlerow_subselect matching a target, replace it with a substitute field used when transforming scalar subqueries into derived tables. More...
virtual Item *	replace_item_field (uchar *)
	Transform processor used by Query_block::transform_grouped_to_derived to replace fields which used to be at the transformed query block with corresponding fields in the new derived table containing the grouping operation of the original transformed query block. More...
virtual Item *	replace_item_view_ref (uchar *)
virtual Item *	replace_aggregate (uchar *)
virtual Item *	replace_outer_ref (uchar *)
virtual bool	update_aggr_refs (uchar *)
	A walker processor overridden by Item_aggregate_ref, q.v. More...
void	delete_self ()
	Delete this item. More...
virtual bool	is_splocal () const
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
	Check whether this and the given item has compatible comparison context. More...
virtual Field::geometry_type	get_geometry_type () const
String *	check_well_formed_result (String *str, bool send_error, bool truncate)
	Verifies that the input string is well-formed according to its character set. More...
bool	eq_by_collation (Item *item, bool binary_cmp, const CHARSET_INFO *cs)
virtual bool	is_expensive ()
uint32	max_char_length () const
uint32	max_char_length (const CHARSET_INFO *cs) const
void	fix_char_length (uint32 max_char_length_arg)
virtual bool	is_outer_field () const
bool	is_blob_field () const
	Check if an item either is a blob field, or will be represented as a BLOB field if a field is created based on this item. More...
uint	reference_count () const
void	increment_ref_count ()
	Increment reference count. More...
uint	decrement_ref_count ()
	Decrement reference count. More...
bool	has_subquery () const
bool	has_stored_program () const
bool	has_aggregation () const
void	set_aggregation ()
	Set the "has aggregation" property. More...
void	reset_aggregation ()
	Reset the "has aggregation" property. More...
bool	has_wf () const
void	set_wf ()
	Set the "has window function" property. More...
bool	has_rollup_expr () const
void	set_rollup_expr ()
	Set the property: this item (tree) contains a reference to a ROLLUP expr. More...
bool	has_grouping_func () const
void	set_grouping_func ()
	Set the property: this item is a call to GROUPING. More...
virtual bool	created_by_in2exists () const
	Whether this Item was created by the IN->EXISTS subquery transformation. More...
void	mark_subqueries_optimized_away ()
virtual bool	gc_subst_analyzer (uchar **)
	Analyzer function for GC substitution. More...
virtual Item *	gc_subst_transformer (uchar *)
	Transformer function for GC substitution. More...
virtual bool	replace_field_processor (uchar *)
	A processor that replaces any Fields with a Create_field_wrapper. More...
bool	can_be_substituted_for_gc (bool array=false) const
	Check if this item is of a type that is eligible for GC substitution. More...
void	aggregate_decimal_properties (Item **item, uint nitems)
	Set precision and decimals of function when this depends on arguments' values for these quantities. More...
void	aggregate_float_properties (Item **item, uint nitems)
	Set max_length and decimals of function if function is floating point and result length/precision depends on argument ones. More...
void	aggregate_char_length (Item **args, uint nitems)
	Set the maximum number of characters required by any of the items in args. More...
void	aggregate_temporal_properties (Item **item, uint nitems)
	Set fractional seconds precision for temporal functions. More...
bool	aggregate_string_properties (const char *name, Item **item, uint nitems)
	Aggregate string properties (character set, collation and maximum length) for string function. More...
void	aggregate_num_type (Item_result result_type, Item **item, uint nitems)
	This function is used to resolve type for numeric result type of CASE, COALESCE, IF and LEAD/LAG. More...
virtual bool	repoint_const_outer_ref (uchar *arg)
	This function applies only to Item_field objects referred to by an Item_ref object that has been marked as a const_item. More...
virtual bool	strip_db_table_name_processor (uchar *)
bool	is_abandoned () const
bool	is_nullable () const
void	set_nullable (bool nullable)
virtual bool	supports_partial_update (const Field_json *field) const
	Check if this expression can be used for partial update of a given JSON column. More...
virtual bool	returns_array () const
	Whether the item returns array of its data type. More...
virtual void	allow_array_cast ()
	A helper function to ensure proper usage of CAST(. More...
Public Member Functions inherited from Parse_tree_node_tmpl< Context >
virtual	~Parse_tree_node_tmpl ()=default
bool	is_contextualized () const
virtual bool	contextualize (Context *pc)
	Do all context-sensitive things and mark the node as contextualized. More...
void	error (Context *pc, const POS &pos) const
	syntax_error() function replacement for deferred reporting of syntax errors More...
void	error (Context *pc, const POS &pos, const char *msg) const
	syntax_error() function replacement for deferred reporting of syntax errors More...
void	errorf (Context *pc, const POS &pos, const char *format,...) const
	syntax_error() function replacement for deferred reporting of syntax errors More...

Private Attributes
const Name_string	func_name

Additional Inherited Members
Public Types inherited from Item
enum	Type {   INVALID_ITEM = 0 , FIELD_ITEM , FUNC_ITEM , SUM_FUNC_ITEM ,   STRING_ITEM , INT_ITEM , REAL_ITEM , NULL_ITEM ,   VARBIN_ITEM , METADATA_COPY_ITEM , FIELD_AVG_ITEM , DEFAULT_VALUE_ITEM ,   PROC_ITEM , COND_ITEM , REF_ITEM , FIELD_STD_ITEM ,   FIELD_VARIANCE_ITEM , INSERT_VALUE_ITEM , SUBSELECT_ITEM , ROW_ITEM ,   CACHE_ITEM , TYPE_HOLDER , PARAM_ITEM , TRIGGER_FIELD_ITEM ,   DECIMAL_ITEM , XPATH_NODESET , XPATH_NODESET_CMP , VIEW_FIXER_ITEM ,   FIELD_BIT_ITEM , VALUES_COLUMN_ITEM }
enum	cond_result { COND_UNDEF , COND_OK , COND_TRUE , COND_FALSE }
enum	traverse_order { POSTFIX , PREFIX }
enum	enum_const_item_cache { CACHE_NONE = 0 , CACHE_JSON_VALUE , CACHE_JSON_ATOM }
	How to cache constant JSON data. More...
enum	Bool_test {   BOOL_IS_TRUE = 0x00 , BOOL_IS_FALSE = 0x01 , BOOL_IS_UNKNOWN = 0x02 , BOOL_NOT_TRUE = 0x03 ,   BOOL_NOT_FALSE = 0x04 , BOOL_NOT_UNKNOWN = 0x05 , BOOL_IDENTITY = 0x06 , BOOL_NEGATED = 0x07 ,   BOOL_ALWAYS_TRUE = 0x08 , BOOL_ALWAYS_FALSE = 0x09 }
	< Modifier for result transformation More...
enum	item_marker {   MARKER_NONE = 0 , MARKER_IMPLICIT_NE_ZERO = 1 , MARKER_CONST_PROPAG = 2 , MARKER_BIT = 4 ,   MARKER_FUNC_DEP_NOT_NULL = 5 , MARKER_DISTINCT_GROUP = 6 , MARKER_COND_DERIVED_TABLE = 7 , MARKER_TRAVERSAL = 8 ,   MARKER_ICP_COND_USES_INDEX_ONLY = 10 }
	< Values for member 'marker' More...
Public Types inherited from Parse_tree_node_tmpl< Context >
typedef Context	context_t
Static Public Member Functions inherited from Item
static void *	operator new (size_t size) noexcept
static void *	operator new (size_t size, MEM_ROOT *mem_root, const std::nothrow_t &arg=std::nothrow) noexcept
static void	operator delete (void *ptr, size_t size)
static void	operator delete (void *, MEM_ROOT *, const std::nothrow_t &) noexcept
static enum_field_types	result_to_type (Item_result result)
static Item_result	type_to_result (enum_field_types type)
static enum_field_types	type_for_variable (enum_field_types src_type)
	Provide data type for a user or system variable, based on the type of the item that is assigned to the variable. More...
static enum_field_types	string_field_type (uint32 max_bytes)
	Determine correct string field type, based on string length. More...
static const CHARSET_INFO *	default_charset ()
Static Public Member Functions inherited from Parse_tree_node_tmpl< Context >
static void *	operator new (size_t size, MEM_ROOT *mem_root, const std::nothrow_t &arg=std::nothrow) noexcept
static void	operator delete (void *ptr, size_t size)
static void	operator delete (void *, MEM_ROOT *, const std::nothrow_t &) noexcept
Public Attributes inherited from Item_float
double	value
Public Attributes inherited from Item
Item *	next_free
	Intrusive list pointer for free list. More...
DTCollation	collation
	Character set and collation properties assigned for this Item. More...
Item_name_string	item_name
	Name from query. More...
Item_name_string	orig_name
	Original item name (if it was renamed) More...
uint32	max_length
	Maximum length of result of evaluating this item, in number of bytes. More...
item_marker	marker
	This member has several successive meanings, depending on the phase we're in (. More...
Item_result	cmp_context
	Comparison context. More...
bool	fixed
	True if item has been resolved. More...
uint8	decimals
	Number of decimals in result when evaluating this item. More...
bool	null_value
	True if item is null. More...
bool	unsigned_flag
bool	m_is_window_function
	True if item represents window func. More...
bool	hidden {false}
	If the item is in a SELECT list (Query_block::fields) and hidden is true, the item wasn't actually in the list as given by the user (it was added by the optimizer, to e.g. More...
bool	m_in_check_constraint_exec_ctx {false}
	True if item is a top most element in the expression being evaluated for a check constraint. More...
Protected Member Functions inherited from Item_float
type_conversion_status	save_in_field_inner (Field *field, bool no_conversions) override
	Helper function which does all of the work for save_in_field(Field*, bool), except some error checking common to all subclasses, which is performed by save_in_field() itself. More...
Protected Member Functions inherited from Item
String *	make_empty_result ()
	Sets the result value of the function an empty string, using the current character set. More...
bool	skip_itemize (Item **res)
	Helper function to skip itemize() for grammar-allocated items. More...
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 ()
longlong	val_int_from_string ()
double	val_real_from_decimal ()
double	val_real_from_string ()
bool	error_bool ()
	Get the value to return from val_bool() in case of errors. More...
int	error_int ()
	Get the value to return from val_int() in case of errors. More...
double	error_real ()
	Get the value to return from val_real() in case of errors. More...
bool	error_date ()
	Get the value to return from get_date() in case of errors. More...
bool	error_time ()
	Get the value to return from get_time() in case of errors. More...
String *	null_return_str ()
	Gets the value to return from val_str() when returning a NULL value. More...
bool	get_date_from_string (MYSQL_TIME *ltime, my_time_flags_t flags)
	Convert val_str() to date in MYSQL_TIME. More...
bool	get_date_from_real (MYSQL_TIME *ltime, my_time_flags_t flags)
	Convert val_real() to date in MYSQL_TIME. More...
bool	get_date_from_decimal (MYSQL_TIME *ltime, my_time_flags_t flags)
	Convert val_decimal() to date in MYSQL_TIME. More...
bool	get_date_from_int (MYSQL_TIME *ltime, my_time_flags_t flags)
	Convert val_int() to date in MYSQL_TIME. More...
bool	get_date_from_time (MYSQL_TIME *ltime)
	Convert get_time() from time to date in MYSQL_TIME. More...
bool	get_date_from_numeric (MYSQL_TIME *ltime, my_time_flags_t fuzzydate)
	Convert a numeric type to date. More...
bool	get_time_from_string (MYSQL_TIME *ltime)
	Convert val_str() to time in MYSQL_TIME. More...
bool	get_time_from_real (MYSQL_TIME *ltime)
	Convert val_real() to time in MYSQL_TIME. More...
bool	get_time_from_decimal (MYSQL_TIME *ltime)
	Convert val_decimal() to time in MYSQL_TIME. More...
bool	get_time_from_int (MYSQL_TIME *ltime)
	Convert val_int() to time in MYSQL_TIME. More...
bool	get_time_from_date (MYSQL_TIME *ltime)
	Convert date to time. More...
bool	get_time_from_datetime (MYSQL_TIME *ltime)
	Convert datetime to time. More...
bool	get_time_from_numeric (MYSQL_TIME *ltime)
	Convert a numeric type to time. More...
virtual longlong	val_date_temporal_at_utc ()
virtual longlong	val_time_temporal_at_utc ()
void	set_accum_properties (const Item *item)
	Set accumulated properties for an Item. More...
void	add_accum_properties (const Item *item)
	Add more accumulated properties to an Item. More...
void	set_subquery ()
	Set the "has subquery" property. More...
void	set_stored_program ()
	Set the "has stored program" property. More...
Protected Member Functions inherited from Parse_tree_node_tmpl< Context >
	Parse_tree_node_tmpl ()
Static Protected Member Functions inherited from Item
static bool	bit_func_returns_binary (const Item *a, const Item *b)
static bool	mark_field_in_map (Mark_field *mark_field, Field *field)
	Helper function for mark_field_in_map(uchar *arg). More...
Protected Attributes inherited from Item
String	str_value
	str_values's main purpose is to cache the value in save_in_field More...
uint8	m_accum_properties
Static Protected Attributes inherited from Item
static constexpr uint8	PROP_SUBQUERY = 0x01
	Set of properties that are calculated by accumulation from underlying items. More...
static constexpr uint8	PROP_STORED_PROGRAM = 0x02
static constexpr uint8	PROP_AGGREGATION = 0x04
static constexpr uint8	PROP_WINDOW_FUNCTION = 0x08
static constexpr uint8	PROP_ROLLUP_EXPR = 0x10
	Set if the item or one or more of the underlying items contains a ROLLUP expression. More...
static constexpr uint8	PROP_GROUPING_FUNC = 0x20
	Set if the item or one or more of the underlying items is a GROUPING function. More...

Constructor & Destructor Documentation

Item_func_pi()

Item_func_pi::Item_func_pi ( const POS &  pos )

inline

Member Function Documentation

print()

void Item_func_pi::print ( const THD *  , String *  str, enum_query_type    ) const

inlineoverridevirtual

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;
• to generate a SQL-query that looks like a prepared statement for query_rewrite
• 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_float.

safe_charset_converter()

Item * Item_func_pi::safe_charset_converter ( THD *  thd, const CHARSET_INFO *  tocs  )

overridevirtual

Created mostly for mysql_prepare_table(). Important when a string ENUM/SET column is described with a numeric default value:

CREATE TABLE t1(a SET('a') DEFAULT 1);

We cannot use generic Item::safe_charset_converter(), because the latter returns a non-fixed Item, so val_str() crashes afterwards. Override Item_num method, to return a fixed item.

Reimplemented from Item_num.

Member Data Documentation

func_name

const Name_string Item_func_pi::func_name

private

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

• sql/item.h
• sql/item.cc