MySQL  8.0.27
Source Code Documentation
Item_ref Class Reference

#include <item.h>

Inheritance diagram for Item_ref:
Item_ident Item Parse_tree_node_tmpl< Context > Item_aggregate_ref Item_outer_ref Item_ref_null_helper Item_view_ref

Public Types

enum  Ref_Type { REF , VIEW_REF , OUTER_REF , AGGREGATE_REF }
 
- 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_ICP_COND_USES_INDEX_ONLY = 10
}
 < Values for member 'marker' More...
 
- Public Types inherited from Parse_tree_node_tmpl< Context >
typedef Context context_t
 

Public Member Functions

 Item_ref (Name_resolution_context *context_arg, const char *db_name_arg, const char *table_name_arg, const char *field_name_arg)
 
 Item_ref (const POS &pos, const char *db_name_arg, const char *table_name_arg, const char *field_name_arg)
 
 Item_ref (Name_resolution_context *context_arg, Item **item, const char *db_name_arg, const char *table_name_arg, const char *field_name_arg, bool alias_of_expr_arg=false)
 
 Item_ref (Name_resolution_context *context_arg, Item **item, const char *field_name_arg)
 
 Item_ref (THD *thd, Item_ref *item)
 
enum Type type () const override
 
bool eq (const Item *item, bool binary_cmp) const override
 
double val_real () override
 
longlong val_int () override
 
longlong val_time_temporal () override
 Return time value of item in packed longlong format. More...
 
longlong val_date_temporal () override
 Return date value of item in packed longlong format. More...
 
my_decimalval_decimal (my_decimal *) override
 
bool val_bool () override
 
Stringval_str (String *tmp) override
 
bool val_json (Json_wrapper *result) override
 
bool is_null () override
 The method allows to determine nullness of a complex expression without fully evaluating it, instead of calling val*() then checking null_value. More...
 
bool get_date (MYSQL_TIME *ltime, my_time_flags_t fuzzydate) override
 
bool send (Protocol *prot, String *tmp) override
 This is only called from items that is not of type item_field. More...
 
void make_field (Send_field *field) override
 
bool fix_fields (THD *, Item **) override
 Resolve the name of a reference to a column reference. More...
 
void fix_after_pullout (Query_block *parent_query_block, Query_block *removed_query_block) override
 
Item_result result_type () const override
 
TYPELIBget_typelib () const override
 Get the typelib information for an item of type set or enum. More...
 
Fieldget_tmp_table_field () override
 If this Item is being materialized into a temporary table, returns the field that is being materialized into. More...
 
Itemget_tmp_table_item (THD *thd) override
 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...
 
table_map used_tables () const override
 
void update_used_tables () override
 Updates used tables, not null tables information and accumulates properties up the item tree, cf. More...
 
table_map not_null_tables () const override
 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...
 
void set_result_field (Field *field) override
 
bool is_result_field () const override
 
Fieldget_result_field () const override
 
Itemreal_item () override
 
const Itemreal_item () const override
 
bool walk (Item_processor processor, enum_walk walk, uchar *arg) override
 
Itemtransform (Item_transformer, uchar *arg) override
 Transform an Item_ref object with a transformer callback function. More...
 
Itemcompile (Item_analyzer analyzer, uchar **arg_p, Item_transformer transformer, uchar *arg_t) override
 Compile an Item_ref object with a processor and a transformer callback function. More...
 
void traverse_cond (Cond_traverser traverser, void *arg, traverse_order order) override
 
bool explain_subquery_checker (uchar **) override
 
void print (const THD *thd, String *str, enum_query_type query_type) const override
 This method is used for to: More...
 
void cleanup () override
 Called for every Item after use (preparation and execution). More...
 
Item_fieldfield_for_view_update () override
 
virtual Ref_Type ref_type () const
 
uint cols () const override
 
Itemelement_index (uint i) override
 
Item ** addr (uint i) override
 
bool check_cols (uint c) override
 
bool null_inside () override
 
void bring_value () override
 
bool get_time (MYSQL_TIME *ltime) override
 
bool basic_const_item () const override
 
bool is_outer_field () const override
 
bool created_by_in2exists () const override
 Whether this Item was created by the IN->EXISTS subquery transformation. More...
 
bool repoint_const_outer_ref (uchar *arg) override
 The aim here is to find a real_item() which is of type Item_field. More...
 
bool is_non_const_over_literals (uchar *) override
 
bool check_function_as_value_generator (uchar *args) override
 Check if this item is allowed for a virtual column or inside a default expression. More...
 
Item_result cast_to_int_type () const override
 
bool check_column_from_derived_table (uchar *arg) override
 
bool check_column_in_window_functions (uchar *arg) override
 
bool check_column_in_group_by (uchar *arg) override
 
bool collect_item_field_or_ref_processor (uchar *arg) override
 
- Public Member Functions inherited from Item_ident
 Item_ident (Name_resolution_context *context_arg, const char *db_name_arg, const char *table_name_arg, const char *field_name_arg)
 
 Item_ident (const POS &pos, const char *db_name_arg, const char *table_name_arg, const char *field_name_arg)
 
 Item_ident (THD *thd, Item_ident *item)
 Constructor used by Item_field & Item_*_ref (see Item comment) More...
 
bool itemize (Parse_context *pc, Item **res) override
 The same as contextualize() but with additional parameter. More...
 
const char * full_name () const override
 
void set_orignal_db_name (const char *name_arg)
 
void set_original_table_name (const char *name_arg)
 
void set_original_field_name (const char *name_arg)
 
const char * original_db_name () const
 
const char * original_table_name () const
 
const char * original_field_name () const
 
void fix_after_pullout (Query_block *parent_query_block, Query_block *removed_query_block) override
 
bool aggregate_check_distinct (uchar *arg) override
 
bool aggregate_check_group (uchar *arg) override
 
Bool3 local_column (const Query_block *sl) const override
 Tells if this is a column of a table whose qualifying query block is 'sl'. More...
 
bool change_context_processor (uchar *arg) override
 
bool is_alias_of_expr () const
 
void set_alias_of_expr ()
 Marks that this Item's name is alias of SELECT expression. More...
 
bool walk (Item_processor processor, enum_walk walk, uchar *arg) override
 
bool update_depended_from (uchar *) override
 
virtual bool alias_name_used () const
 
bool is_strong_side_column_not_in_fd (uchar *arg) override
 
bool is_column_not_in_fd (uchar *arg) override
 
- 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
 
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 Fieldmake_string_field (TABLE *table) const
 Create a field to hold a string value from an item. More...
 
virtual void fix_after_pullout (Query_block *parent_query_block[[maybe_unused]], Query_block *removed_query_block[[maybe_unused]])
 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[[maybe_unused]], const Type_properties &type[[maybe_unused]])
 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...
 
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)
 
bool evaluate (THD *thd, String *str)
 Evaluate item, possibly using the supplied buffer. More...
 
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_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...
 
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[[maybe_unused]], bool *incl_endp[[maybe_unused]])
 
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 Stringval_str_ascii (String *str)
 
virtual bool val_json (Json_wrapper *result[[maybe_unused]])
 Get a JSON value from an Item. More...
 
virtual float get_filtering_effect (THD *thd[[maybe_unused]], table_map filter_for_table[[maybe_unused]], table_map read_tables[[maybe_unused]], const MY_BITMAP *fields_to_ignore[[maybe_unused]], double rows_in_table[[maybe_unused]])
 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_decimalerror_decimal (my_decimal *decimal_value)
 Get the value to return from val_decimal() in case of errors. More...
 
Stringerror_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 Fieldtmp_table_field (TABLE *)
 
bool may_eval_const_item (const THD *thd) const
 
virtual Itemclone_item () 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 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 (struct timeval *tm, int *warnings)
 Get timestamp in "struct timeval" format. 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 bool is_bool_func () const
 
virtual void no_rows_in_result ()
 
virtual Itemcopy_or_same (THD *)
 
virtual Itemcopy_andor_structure (THD *)
 
virtual const CHARSET_INFOcompare_collation () const
 
virtual const CHARSET_INFOcharset_for_protocol ()
 
virtual bool walk (Item_processor processor, enum_walk walk[[maybe_unused]], 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 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_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[[maybe_unused]])
 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 find_item_processor (uchar *arg)
 
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[[maybe_unused]])
 Mark underlying field in read or write map of a table. More...
 
virtual bool ensure_multi_equality_fields_are_available_walker (uchar *)
 Traverse the item tree and replace fields that are outside of reach with fields that are within reach. More...
 
virtual bool reset_wf_state (uchar *arg[[maybe_unused]])
 Reset execution state for such window function types as determined by arg. More...
 
virtual bool used_tables_for_level (uchar *arg[[maybe_unused]])
 Return used table information for the specified query block (level). More...
 
virtual bool check_column_privileges (uchar *thd[[maybe_unused]])
 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 *)
 Clean up after removing the item from the item tree. More...
 
bool propagate_derived_used (uchar *)
 Propagate components that use referenced columns from derived tables. More...
 
bool propagate_set_derived_used (uchar *)
 Called by Item::walk() to set all the referenced items' derived_used flag. More...
 
virtual bool collect_scalar_subqueries (uchar *)
 
virtual bool collect_grouped_aggregates (uchar *)
 
virtual bool collect_subqueries (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...
 
Itemcache_const_expr_transformer (uchar *item)
 Cache item if needed. More...
 
virtual bool equality_substitution_analyzer (uchar **)
 
virtual Itemequality_substitution_transformer (uchar *)
 
virtual bool check_partition_func_processor (uchar *)
 Check if a partition function is allowed. More...
 
virtual bool subst_argument_checker (uchar **arg)
 
virtual Itemexplain_subquery_propagator (uchar *)
 
virtual Itemequal_fields_propagator (uchar *)
 
virtual bool disable_constant_propagation (uchar *)
 
virtual Itemreplace_equal_field (uchar *)
 
virtual bool check_valid_arguments_processor (uchar *)
 
virtual bool check_gcol_depend_default_processor (uchar *args[[maybe_unused]])
 Check if a generated expression depends on DEFAULT function with specific column name as argument. More...
 
virtual bool check_column_from_derived_table (uchar *arg[[maybe_unused]])
 Check if all the columns present in this expression are from the derived table. More...
 
virtual bool check_column_in_window_functions (uchar *arg[[maybe_unused]])
 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[[maybe_unused]])
 Check if all the columns present in this expression are present in GROUP BY clause of the derived table. More...
 
virtual Itemreplace_with_derived_expr (uchar *arg[[maybe_unused]])
 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 Itemreplace_with_derived_expr_ref (uchar *arg[[maybe_unused]])
 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 Itemreplace_view_refs_with_clone (uchar *arg[[maybe_unused]])
 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 Itemthis_item ()
 
virtual const Itemthis_item () const
 
virtual Item ** this_item_addr (THD *, Item **addr_arg)
 
Fieldtmp_table_field_from_field_type (TABLE *table, bool fixed_length) const
 Create a field based on field_type of argument. More...
 
virtual Itemtruth_transformer (THD *thd[[maybe_unused]], Bool_test test[[maybe_unused]])
 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 Itemupdate_value_transformer (uchar *)
 
virtual Itemreplace_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 Itemreplace_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 Itemreplace_item_view_ref (uchar *)
 
virtual Itemreplace_aggregate (uchar *)
 
virtual Itemreplace_outer_ref (uchar *)
 
virtual bool update_aggr_refs (uchar *)
 A walker processor overridden by Item_aggregate_ref, q.v. More...
 
virtual Itemsafe_charset_converter (THD *thd, const CHARSET_INFO *tocs)
 
void delete_self ()
 Delete this item. More...
 
virtual bool is_splocal () const
 
virtual Settable_routine_parameterget_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
 
Stringcheck_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)
 
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...
 
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...
 
bool is_derived_used () const
 
void mark_subqueries_optimized_away ()
 
virtual bool gc_subst_analyzer (uchar **)
 Analyzer function for GC substitution. More...
 
virtual Itemgc_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[[maybe_unused]])
 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_nullable () const
 
void set_nullable (bool nullable)
 
virtual bool supports_partial_update (const Field_json *field[[maybe_unused]]) 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 funciton 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...
 

Public Attributes

bool pusheddown_depended_from {false}
 
Item ** ref
 
- Public Attributes inherited from Item_ident
Name_resolution_contextcontext
 For regularly resolved column references, 'context' points to a name resolution context object belonging to the query block which simply contains the reference. More...
 
const char * db_name
 Schema name of the base table or view the column is part of. More...
 
const char * table_name
 If column is from a non-aliased base table or view, name of base table or view. More...
 
const char * field_name
 If column is aliased, the column alias name. More...
 
TABLE_LISTcached_table
 
Query_blockdepended_from
 
- Public Attributes inherited from Item
Itemnext_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

void set_properties ()
 
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_ident
void print (const THD *thd, String *str, enum_query_type query_type, const char *db_name_arg, const char *table_name_arg) const
 Function to print column name for a table. More...
 
- Protected Member Functions inherited from Item
Stringmake_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...
 
Stringval_string_from_real (String *str)
 
Stringval_string_from_int (String *str)
 
Stringval_string_from_decimal (String *str)
 
Stringval_string_from_date (String *str)
 
Stringval_string_from_datetime (String *str)
 
Stringval_string_from_time (String *str)
 
my_decimalval_decimal_from_real (my_decimal *decimal_value)
 
my_decimalval_decimal_from_int (my_decimal *decimal_value)
 
my_decimalval_decimal_from_string (my_decimal *decimal_value)
 
my_decimalval_decimal_from_date (my_decimal *decimal_value)
 
my_decimalval_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...
 
Stringnull_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 ()
 

Private Attributes

Fieldresult_field {nullptr}
 

Additional Inherited Members

- 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[[maybe_unused]]=std::nothrow) noexcept
 
static void operator delete (void *ptr[[maybe_unused]], size_t size[[maybe_unused]])
 
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_INFOdefault_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[[maybe_unused]]=std::nothrow) noexcept
 
static void operator delete (void *ptr[[maybe_unused]], size_t size[[maybe_unused]])
 
static void operator delete (void *, MEM_ROOT *, const std::nothrow_t &) noexcept
 
- 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_ident
const char * m_orig_db_name
 The fields m_orig_db_name, m_orig_table_name and m_orig_field_name are maintained so that we can provide information about the origin of a column that may have been renamed within the query, e.g. More...
 
const char * m_orig_table_name
 Names the original table that is the source of the field. More...
 
const char * m_orig_field_name
 Names the field in the source base table. More...
 
bool m_alias_of_expr
 if this Item's name is alias of SELECT expression 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...
 

Member Enumeration Documentation

◆ Ref_Type

Enumerator
REF 
VIEW_REF 
OUTER_REF 
AGGREGATE_REF 

Constructor & Destructor Documentation

◆ Item_ref() [1/5]

Item_ref::Item_ref ( Name_resolution_context context_arg,
const char *  db_name_arg,
const char *  table_name_arg,
const char *  field_name_arg 
)
inline

◆ Item_ref() [2/5]

Item_ref::Item_ref ( const POS pos,
const char *  db_name_arg,
const char *  table_name_arg,
const char *  field_name_arg 
)
inline

◆ Item_ref() [3/5]

Item_ref::Item_ref ( Name_resolution_context context_arg,
Item **  item,
const char *  db_name_arg,
const char *  table_name_arg,
const char *  field_name_arg,
bool  alias_of_expr_arg = false 
)

◆ Item_ref() [4/5]

Item_ref::Item_ref ( Name_resolution_context context_arg,
Item **  item,
const char *  field_name_arg 
)

◆ Item_ref() [5/5]

Item_ref::Item_ref ( THD thd,
Item_ref item 
)
inline

Member Function Documentation

◆ addr()

Item** Item_ref::addr ( uint  i)
inlineoverridevirtual

Reimplemented from Item.

◆ basic_const_item()

bool Item_ref::basic_const_item ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ bring_value()

void Item_ref::bring_value ( )
inlineoverridevirtual

Reimplemented from Item.

◆ cast_to_int_type()

Item_result Item_ref::cast_to_int_type ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ check_cols()

bool Item_ref::check_cols ( uint  c)
inlineoverridevirtual

Reimplemented from Item.

◆ check_column_from_derived_table()

bool Item_ref::check_column_from_derived_table ( uchar arg)
inlineoverride

◆ check_column_in_group_by()

bool Item_ref::check_column_in_group_by ( uchar arg)
inlineoverride

◆ check_column_in_window_functions()

bool Item_ref::check_column_in_window_functions ( uchar arg)
inlineoverride

◆ check_function_as_value_generator()

bool Item_ref::check_function_as_value_generator ( uchar args)
inlineoverridevirtual

Check if this item is allowed for a virtual column or inside a default expression.

Should be overridden in child classes.

Parameters
[in,out]argsDue to the limitation of Item::walk() it is declared as a pointer to uchar, underneath there's a actually a structure of type Check_function_as_value_generator_parameters. It is used mainly in Item_field.
Returns
true if function is not accepted

Reimplemented from Item.

◆ cleanup()

void Item_ref::cleanup ( )
overridevirtual

Called for every Item after use (preparation and execution).

Release all allocated resources, such as dynamic memory. Prepare for new execution by clearing cached values. Do not remove values allocated during preparation, destructor handles this.

Reimplemented from Item.

◆ collect_item_field_or_ref_processor()

bool Item_ref::collect_item_field_or_ref_processor ( uchar arg)
overridevirtual

Reimplemented from Item.

◆ cols()

uint Item_ref::cols ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ compile()

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

Compile an Item_ref object with a processor and a transformer callback function.

First the function applies the analyzer to the Item_ref object. Second it applies the compile function to the object the Item_ref object is referencing. If this replaces the item with a new one, this object is returned as the result of the compile. Otherwise we apply the transformer to the Item_ref object itself.

Reimplemented from Item.

◆ created_by_in2exists()

bool Item_ref::created_by_in2exists ( ) const
inlineoverridevirtual

Whether this Item was created by the IN->EXISTS subquery transformation.

Reimplemented from Item.

◆ element_index()

Item* Item_ref::element_index ( uint  i)
inlineoverridevirtual

Reimplemented from Item.

◆ eq()

bool Item_ref::eq ( const Item item,
bool  binary_cmp 
) const
inlineoverridevirtual

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_view_ref.

◆ explain_subquery_checker()

bool Item_ref::explain_subquery_checker ( uchar **  )
inlineoverridevirtual

Reimplemented from Item.

◆ field_for_view_update()

Item_field* Item_ref::field_for_view_update ( )
inlineoverridevirtual

Reimplemented from Item.

◆ fix_after_pullout()

void Item_ref::fix_after_pullout ( Query_block parent_query_block,
Query_block removed_query_block 
)
override

◆ fix_fields()

bool Item_ref::fix_fields ( THD thd,
Item **  reference 
)
overridevirtual

Resolve the name of a reference to a column reference.

The method resolves the column reference represented by 'this' as a column present in one of: GROUP BY clause, SELECT clause, outer queries. It is used typically for columns in the HAVING clause which are not under aggregate functions.

POSTCONDITION
Item_ref::ref is 0 or points to a valid item.

Note
The name resolution algorithm used is (where [T_j] is an optional table name that qualifies the column name):
resolve_extended([T_j].col_ref_i)
{
Search for a column or derived column named col_ref_i [in table T_j]
in the SELECT and GROUP clauses of Q.
if such a column is NOT found AND // Lookup in outer queries.
there are outer queries
{
for each outer query Q_k beginning from the inner-most one
{
Search for a column or derived column named col_ref_i
[in table T_j] in the SELECT and GROUP clauses of Q_k.
if such a column is not found AND
- Q_k is not a group query AND
- Q_k is not inside an aggregate function
OR
- Q_(k-1) is not in a HAVING or SELECT clause of Q_k
{
search for a column or derived column named col_ref_i
[in table T_j] in the FROM clause of Q_k;
}
}
}
}
static char * query
Definition: myisam_ftdump.cc:44
const std::string SELECT("SELECT")
Name of the static privileges.
@ FROM
Definition: sql_yacc.h:242
@ HAVING
Definition: sql_yacc.h:262


This procedure treats GROUP BY and SELECT clauses as one namespace for column references in HAVING. Notice that compared to Item_field::fix_fields, here we first search the SELECT and GROUP BY clauses, and then we search the FROM clause.

Parameters
[in]thdcurrent thread
[in,out]referenceview column if this item was resolved to a view column
Return values
trueif error
falseon success

Reimplemented from Item.

Reimplemented in Item_outer_ref, and Item_view_ref.

◆ get_date()

bool Item_ref::get_date ( MYSQL_TIME ltime,
my_time_flags_t  fuzzydate 
)
overridevirtual

Implements Item.

Reimplemented in Item_ref_null_helper.

◆ get_result_field()

Field* Item_ref::get_result_field ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ get_time()

bool Item_ref::get_time ( MYSQL_TIME ltime)
inlineoverridevirtual

Implements Item.

◆ get_tmp_table_field()

Field* Item_ref::get_tmp_table_field ( )
inlineoverridevirtual

If this Item is being materialized into a temporary table, returns the field that is being materialized into.

(Typically, this is the “result_field” members for items that have one.)

Reimplemented from Item.

◆ get_tmp_table_item()

Item * Item_ref::get_tmp_table_item ( THD thd)
overridevirtual

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.

For instance, if the Item was an Item_field, the new Item_field needs to point into the temporary table instead of the original one, but if, on the other hand, the Item was a literal constant, it can be reused as-is. This function encapsulates these policies for the different kinds of Items. See also get_tmp_table_field().

TODO: Document how aggregate functions (Item_sum) are handled.

Reimplemented from Item.

Reimplemented in Item_view_ref.

◆ get_typelib()

TYPELIB* Item_ref::get_typelib ( ) const
inlineoverridevirtual

Get the typelib information for an item of type set or enum.

Reimplemented from Item.

◆ is_non_const_over_literals()

bool Item_ref::is_non_const_over_literals ( uchar )
inlineoverridevirtual

Reimplemented from Item.

◆ is_null()

bool Item_ref::is_null ( )
overridevirtual

The method allows to determine nullness of a complex expression without fully evaluating it, instead of calling val*() then checking null_value.

Used in Item_func_isnull/Item_func_isnotnull and Item_sum_count/Item_sum_count_distinct. Any item which can be NULL must implement this method.

Return values
falseif the expression is not NULL.
trueif the expression is NULL, or evaluation caused an error. The null_value member is set according to the return value.

Reimplemented from Item.

Reimplemented in Item_view_ref.

◆ is_outer_field()

bool Item_ref::is_outer_field ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ is_result_field()

bool Item_ref::is_result_field ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ make_field()

void Item_ref::make_field ( Send_field field)
overridevirtual

Reimplemented from Item.

◆ not_null_tables()

table_map Item_ref::not_null_tables ( ) const
inlineoverridevirtual

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).

This expression is used on WHERE item to determinate if a LEFT JOIN can be converted to a normal join. Generally this function should return used_tables() if the function would return null if any of the arguments are null As this is only used in the beginning of optimization, the value don't have to be updated in update_used_tables()

Reimplemented from Item.

Reimplemented in Item_outer_ref.

◆ null_inside()

bool Item_ref::null_inside ( )
inlineoverridevirtual

Reimplemented from Item.

◆ print()

void Item_ref::print ( const THD ,
String str,
enum_query_type   
) const
overridevirtual

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_ident.

Reimplemented in Item_ref_null_helper.

◆ real_item() [1/2]

const Item* Item_ref::real_item ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ real_item() [2/2]

Item* Item_ref::real_item ( )
inlineoverridevirtual
Returns
the "real item" underlying the owner object. Used to strip away Item_ref objects.
Note
remember to implement both real_item() functions in sub classes!

Reimplemented from Item.

◆ ref_type()

virtual Ref_Type Item_ref::ref_type ( ) const
inlinevirtual

◆ repoint_const_outer_ref()

bool Item_ref::repoint_const_outer_ref ( uchar arg)
override

The aim here is to find a real_item() which is of type Item_field.

◆ result_type()

Item_result Item_ref::result_type ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ save_in_field_inner()

type_conversion_status Item_ref::save_in_field_inner ( Field field,
bool  no_conversions 
)
overrideprotectedvirtual

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.

Subclasses that need to specialize the behaviour of save_in_field(), should override this function instead of save_in_field().

Parameters
[in,out]fieldthe field to save the item into
no_conversionswhether or not to allow conversions of the value
Returns
the status from saving into the field
Return values
TYPE_OKitem saved without any errors or warnings
!=TYPE_OK there were errors or warnings when saving the item

Reimplemented from Item.

Reimplemented in Item_view_ref.

◆ send()

bool Item_ref::send ( Protocol protocol,
String str 
)
overridevirtual

This is only called from items that is not of type item_field.

Reimplemented from Item.

Reimplemented in Item_view_ref.

◆ set_properties()

void Item_ref::set_properties ( )
protected

◆ set_result_field()

void Item_ref::set_result_field ( Field field)
inlineoverridevirtual

Reimplemented from Item.

◆ transform()

Item * Item_ref::transform ( Item_transformer  transformer,
uchar arg 
)
overridevirtual

Transform an Item_ref object with a transformer callback function.

The function first applies the transform function to the item referenced by this Item_ref object. If this replaces the item with a new one, this item object is returned as the result of the transform. Otherwise the transform function is applied to the Item_ref object itself.

Reimplemented from Item.

◆ traverse_cond()

void Item_ref::traverse_cond ( Cond_traverser  traverser,
void *  arg,
traverse_order  order 
)
inlineoverridevirtual

Reimplemented from Item.

◆ type()

enum Type Item_ref::type ( ) const
inlineoverridevirtual

Implements Item.

◆ update_used_tables()

void Item_ref::update_used_tables ( )
inlineoverridevirtual

Updates used tables, not null tables information and accumulates properties up the item tree, cf.

used_tables_cache, not_null_tables_cache and m_accum_properties.

Reimplemented from Item.

◆ used_tables()

table_map Item_ref::used_tables ( ) const
inlineoverridevirtual

Reimplemented from Item.

Reimplemented in Item_ref_null_helper, Item_outer_ref, and Item_view_ref.

◆ val_bool()

bool Item_ref::val_bool ( )
overridevirtual

Reimplemented from Item.

Reimplemented in Item_ref_null_helper, and Item_view_ref.

◆ val_date_temporal()

longlong Item_ref::val_date_temporal ( )
overridevirtual

Return date value of item in packed longlong format.

Reimplemented from Item.

Reimplemented in Item_ref_null_helper.

◆ val_decimal()

my_decimal * Item_ref::val_decimal ( my_decimal decimal_value)
overridevirtual

Implements Item.

Reimplemented in Item_view_ref, and Item_ref_null_helper.

◆ val_int()

longlong Item_ref::val_int ( void  )
overridevirtual

Implements Item.

Reimplemented in Item_ref_null_helper, and Item_view_ref.

◆ val_json()

bool Item_ref::val_json ( Json_wrapper result)
override

◆ val_real()

double Item_ref::val_real ( void  )
overridevirtual

Implements Item.

Reimplemented in Item_ref_null_helper, and Item_view_ref.

◆ val_str()

String * Item_ref::val_str ( String tmp)
overridevirtual

Implements Item.

Reimplemented in Item_view_ref, and Item_ref_null_helper.

◆ val_time_temporal()

longlong Item_ref::val_time_temporal ( )
overridevirtual

Return time value of item in packed longlong format.

Reimplemented from Item.

Reimplemented in Item_ref_null_helper.

◆ walk()

bool Item_ref::walk ( Item_processor  processor,
enum_walk  walk,
uchar arg 
)
inlineoverride

Member Data Documentation

◆ pusheddown_depended_from

bool Item_ref::pusheddown_depended_from {false}

◆ ref

Item** Item_ref::ref

◆ result_field

Field* Item_ref::result_field {nullptr}
private

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