MySQL 9.0.0
Source Code Documentation
Item_values_column Class Referencefinal

Reference item that encapsulates both the type and the contained items of a single column of a VALUES ROW query expression. More...

#include <item.h>

Inheritance diagram for Item_values_column:
[legend]

Public Member Functions

 Item_values_column (THD *thd, Item *ref)
 
bool eq (const Item *item) const override
 Compare this item with another item for equality. More...
 
double val_real () override
 
longlong val_int () override
 
my_decimalval_decimal (my_decimal *) override
 
bool val_bool () override
 
Stringval_str (String *tmp) override
 
bool val_json (Json_wrapper *result) override
 Get a JSON value from an Item. More...
 
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 get_time (MYSQL_TIME *ltime) override
 
enum Type type () const override
 
void set_value (Item *new_value)
 
table_map used_tables () const override
 
void add_used_tables (Item *value)
 
- Public Member Functions inherited from Item_aggregate_type
 Item_aggregate_type (THD *, Item *)
 
Item_result result_type () const override
 Return expression type of Item_aggregate_type. More...
 
bool join_types (THD *, Item *)
 Find field type which can carry current Item_aggregate_type type and type of given Item. More...
 
Fieldmake_field_by_type (TABLE *table, bool strict)
 Make temporary table field according collected information about type of UNION result. More...
 
Field::geometry_type get_geometry_type () const override
 
void make_field (Send_field *field) 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...
 
- 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) final
 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 cleanup ()
 Called for every Item after use (preparation and execution). More...
 
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 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< ContainedSubqueryget_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 scalar item, possibly using the supplied buffer. More...
 
const Itemunwrap_for_eq () const
 Unwrap an Item argument so that Item::eq() can see the "real" item, and not just the wrapper. 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_null ()
 
void set_data_type_bool ()
 
void set_data_type_int (enum_field_types type, bool unsigned_prop, uint32 max_width)
 Set the data type of the Item to be a specific integer type. More...
 
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 (enum_field_types type, 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_vector (uint32 max_l)
 Set the data type of the Item to be VECTOR. 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 (uint32 max_bits)
 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 TYPELIBget_typelib () const
 Get the typelib information for an item of type set or enum. More...
 
virtual Item_result cast_to_int_type () const
 
bool aggregate_type (const char *name, Item **items, uint count)
 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 Stringval_str_ascii (String *str)
 
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_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 Fieldget_tmp_table_field ()
 If this Item is being materialized into a temporary table, returns the field that is being materialized into. More...
 
virtual Fieldtmp_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...
 
virtual bool basic_const_item () const
 Returns true if this is a simple constant item like an integer, not a constant expression. More...
 
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
 
virtual void print (const THD *, String *str, enum_query_type) const
 This method is used for to: More...
 
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, const char *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 bool split_sum_func (THD *, Ref_item_array, mem_root_deque< Item * > *)
 
bool 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...
 
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 Fieldget_result_field () const
 
virtual bool is_bool_func () const
 
virtual void no_rows_in_result ()
 
virtual Itemcopy_or_same (THD *)
 
virtual Itemcopy_andor_structure (THD *)
 
virtual Itemreal_item ()
 
virtual const Itemreal_item () const
 
virtual Itemget_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_INFOcompare_collation () const
 
virtual const CHARSET_INFOcharset_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 Itemtransform (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 Itemcompile (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...
 
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 bool explain_subquery_checker (uchar **)
 
virtual Itemexplain_subquery_propagator (uchar *)
 
virtual Itemequal_fields_propagator (uchar *)
 
virtual bool disable_constant_propagation (uchar *)
 
virtual Itemreplace_equal_field (uchar *)
 
virtual bool replace_equal_field_checker (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 Itemreplace_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 Itemreplace_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 Itemreplace_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 Itemthis_item ()
 
virtual const Itemthis_item () const
 
virtual Item ** this_item_addr (THD *, Item **addr_arg)
 
virtual uint cols () const
 
virtual Itemelement_index (uint)
 
virtual Item ** addr (uint)
 
virtual bool check_cols (uint c)
 
virtual bool null_inside ()
 
virtual void bring_value ()
 
Fieldtmp_table_field_from_field_type (TABLE *table, bool fixed_length) const
 Create a field based on field_type of argument. More...
 
virtual Item_fieldfield_for_view_update ()
 
virtual Itemtruth_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 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_func_call (uchar *)
 
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...
 
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, const CHARSET_INFO *cs)
 Compare two items using a given collation. More...
 
CostOfItem cost () const
 
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_grouping_set_dep () const
 
void set_group_by_modifier ()
 Set the property: this item (tree) contains a reference to a GROUP BY modifier (such as ROLLUP) 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 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_float_properties (enum_field_types type, Item **items, 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_decimal_properties (Item **items, uint nitems)
 Set data type, precision and scale of item of type decimal from list of items. More...
 
uint32 aggregate_char_width (Item **items, uint nitems)
 Calculate the maximum number of characters required by any of the items. More...
 
void aggregate_temporal_properties (enum_field_types type, Item **items, uint nitems)
 Set data type and fractional seconds precision for temporal functions. More...
 
bool aggregate_string_properties (enum_field_types type, const char *name, Item **items, uint nitems)
 Aggregate string properties (character set, collation and maximum length) for string function. More...
 
void aggregate_bit_properties (Item **items, uint nitems)
 Set data type and properties of a BIT column. 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 *)
 
virtual void compute_cost (CostOfItem *root_cost) const
 Compute the cost of evaluating this Item. More...
 
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) final
 
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 Types

typedef Item_aggregate_type super
 

Private Member Functions

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...
 

Private Attributes

Itemm_value_ref {nullptr}
 
table_map m_aggregated_used_tables {RAND_TABLE_BIT}
 

Additional Inherited Members

- Public Types inherited from Item
enum  Type {
  INVALID_ITEM , FIELD_ITEM , FUNC_ITEM , SUM_FUNC_ITEM ,
  AGGR_FIELD_ITEM , STRING_ITEM , INT_ITEM , DECIMAL_ITEM ,
  REAL_ITEM , NULL_ITEM , HEX_BIN_ITEM , DEFAULT_VALUE_ITEM ,
  COND_ITEM , REF_ITEM , INSERT_VALUE_ITEM , SUBQUERY_ITEM ,
  ROW_ITEM , CACHE_ITEM , TYPE_HOLDER_ITEM , PARAM_ITEM ,
  ROUTINE_FIELD_ITEM , TRIGGER_FIELD_ITEM , XPATH_NODESET_ITEM , VALUES_COLUMN_ITEM ,
  NAME_CONST_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_aggregate_type
static uint32 display_length (Item *item)
 Calculate length for merging result for given Item type. More...
 
- 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_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=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
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...
 
- Public Attributes inherited from Parse_tree_node_tmpl< Context >
POS m_pos
 
- Protected Member Functions inherited from Item_aggregate_type
void set_typelib (Item *item)
 Set typelib information for an aggregated enum/set field. 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...
 
virtual bool do_itemize (Parse_context *pc, Item **res)
 The core function that does the actual itemization. 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...
 
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...
 
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 ()=delete
 
 Parse_tree_node_tmpl (const POS &pos)
 
 Parse_tree_node_tmpl (const POS &start_pos, const POS &end_pos)
 
bool begin_parse_tree (Show_parse_tree *tree)
 
bool end_parse_tree (Show_parse_tree *tree)
 
virtual bool do_contextualize (Context *pc)
 Do all context-sensitive things and mark the node as contextualized. More...
 
virtual void add_json_info (Json_object *json_obj)
 Add all the node-specific json fields. More...
 
- 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_aggregate_type
TYPELIBm_typelib {nullptr}
 Typelib information, only used for data type ENUM and SET. More...
 
Field::geometry_type geometry_type
 Geometry type, only used for data type GEOMETRY. 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_HAS_GROUPING_SET_DEP = 0x10
 Set if the item or one or more of the underlying items contains a GROUP BY modifier (such as ROLLUP). 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...
 

Detailed Description

Reference item that encapsulates both the type and the contained items of a single column of a VALUES ROW query expression.

During execution, the item that will be output for the current iteration is contained in m_value_ref. The type of the column and the referenced item may differ in cases where a column of a VALUES clause contains different types across different rows, and must therefore do type conversions to their common denominator (e.g. a column containing both 10 and "10", of which the types will be aggregated into VARCHAR).

See the class comment for TableValueConstructorIterator for info on how Item_values_column is used as an indirection to iterate over the rows of a table value constructor (i.e. VALUES ROW expressions).

Member Typedef Documentation

◆ super

Constructor & Destructor Documentation

◆ Item_values_column()

Item_values_column::Item_values_column ( THD thd,
Item ref 
)

Member Function Documentation

◆ add_used_tables()

void Item_values_column::add_used_tables ( Item value)

◆ eq()

bool Item_values_column::eq ( const Item item) const
overridevirtual

Compare this item with another item for equality.

If both pointers are the same, the items are equal. Both items must be of same type. For literal values, metadata must be the same and the values must be equal. Strings are compared with the embedded collation. For column references, table references and column names must be the same. For functions, the function type, function properties and arguments must be equal. Otherwise, see specific implementations.

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_multi_eq)

Reimplemented from Item.

◆ get_date()

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

Implements Item_aggregate_type.

◆ get_time()

bool Item_values_column::get_time ( MYSQL_TIME ltime)
overridevirtual

Implements Item_aggregate_type.

◆ is_null()

bool Item_values_column::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.

◆ save_in_field_inner()

type_conversion_status Item_values_column::save_in_field_inner ( Field field,
bool  no_conversions 
)
overrideprivatevirtual

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.

◆ set_value()

void Item_values_column::set_value ( Item new_value)
inline

◆ type()

enum Type Item_values_column::type ( ) const
inlineoverridevirtual

Implements Item.

◆ used_tables()

table_map Item_values_column::used_tables ( ) const
inlineoverridevirtual

Reimplemented from Item.

◆ val_bool()

bool Item_values_column::val_bool ( )
overridevirtual

Reimplemented from Item.

◆ val_decimal()

my_decimal * Item_values_column::val_decimal ( my_decimal decimal_value)
overridevirtual

Implements Item_aggregate_type.

◆ val_int()

longlong Item_values_column::val_int ( void  )
overridevirtual

Implements Item_aggregate_type.

◆ val_json()

bool Item_values_column::val_json ( Json_wrapper result)
overridevirtual

Get a JSON value from an Item.

All subclasses that can return a JSON value, should override this function. The function in the base class is not expected to be called. If it is called, it most likely means that some subclass is missing an override of val_json().

Parameters
[in,out]resultThe resulting Json_wrapper.
Returns
false if successful, true on failure

Reimplemented from Item.

◆ val_real()

double Item_values_column::val_real ( void  )
overridevirtual

Implements Item_aggregate_type.

◆ val_str()

String * Item_values_column::val_str ( String tmp)
overridevirtual

Implements Item_aggregate_type.

Member Data Documentation

◆ m_aggregated_used_tables

table_map Item_values_column::m_aggregated_used_tables {RAND_TABLE_BIT}
private

◆ m_value_ref

Item* Item_values_column::m_value_ref {nullptr}
private

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