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MySQL 9.1.0
Source Code Documentation
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MySQL 9.1.0
Source Code Documentation
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Represents [schema. More...
#include <item.h>
Public Member Functions | |
| Item_asterisk (const POS &pos, const char *opt_schema_name, const char *opt_table_name) | |
| Constructor. More... | |
| bool | do_itemize (Parse_context *pc, Item **res) override |
| The core function that does the actual itemization. More... | |
| bool | fix_fields (THD *, Item **) override |
| Resolve the name of a column reference. More... | |
| bool | is_asterisk () const override |
| Checks if the current object represents an asterisk select list item. More... | |
 Public Member Functions inherited from Item_field | |
| Item_multi_eq * | multi_equality () const |
| void | set_item_equal_all_join_nests (Item_multi_eq *item_equal) |
| Item_field (Name_resolution_context *context_arg, const char *db_arg, const char *table_name_arg, const char *field_name_arg) | |
| Constructor used for internal information queries. More... | |
| Item_field (const POS &pos, const char *db_arg, const char *table_name_arg, const char *field_name_arg) | |
| Used from parser to construct column references. More... | |
| Item_field (THD *thd, Item_field *item) | |
| Used to create a copy (clone) of another Item_field. More... | |
| Item_field (THD *thd, Name_resolution_context *context_arg, Field *field) | |
| Constructor used inside setup_wild(). More... | |
| Item_field (Field *field) | |
| Create column reference based on a table field. More... | |
| enum Type | type () const override |
| bool | eq (const Item *item) const override |
| Compare this item with another item for equality. More... | |
| 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... | |
| longlong | val_time_temporal_at_utc () override |
| longlong | val_date_temporal_at_utc () override |
| my_decimal * | val_decimal (my_decimal *) override |
| String * | val_str (String *) override |
| bool | val_json (Json_wrapper *result) override |
| Get a JSON value from an Item. More... | |
| bool | send (Protocol *protocol, String *str_arg) override |
| This is only called from items that is not of type item_field. More... | |
| void | reset_field (Field *f) |
| Reset this item to point to a field from the new temporary table. More... | |
| void | make_field (Send_field *tmp_field) override |
| void | save_org_in_field (Field *field) override |
| Set a field's value from a item. More... | |
| table_map | used_tables () const override |
| Item_result | result_type () const override |
| Item_result | numeric_context_result_type () const override |
| Result type when an item appear in a numeric context. More... | |
| TYPELIB * | get_typelib () const override |
| Get the typelib information for an item of type set or enum. More... | |
| Item_result | cast_to_int_type () const override |
| enum_monotonicity_info | get_monotonicity_info () const override |
| longlong | val_int_endpoint (bool left_endp, bool *incl_endp) override |
| void | set_result_field (Field *field_arg) override |
| Field * | get_tmp_table_field () override |
| If this Item is being materialized into a temporary table, returns the field that is being materialized into. More... | |
| Field * | tmp_table_field (TABLE *) override |
| void | set_base_item_field (const Item_field *item) |
| const Item_field * | base_item_field () const |
| bool | get_date (MYSQL_TIME *ltime, my_time_flags_t fuzzydate) override |
| bool | get_time (MYSQL_TIME *ltime) override |
| bool | get_timeval (my_timeval *tm, int *warnings) override |
| Get timestamp in "struct timeval" format. 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... | |
| Item * | get_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... | |
| bool | collect_item_field_processor (uchar *arg) override |
| Store the pointer to this item field into a list if not already there. More... | |
| bool | collect_item_field_or_ref_processor (uchar *arg) override |
| When collecting information about columns when transforming correlated scalar subqueries using derived tables, we need to decide which duplicates, if any, to retain: More... | |
| bool | collect_item_field_or_view_ref_processor (uchar *arg) override |
| Collects fields and view references that have the qualifying table in the specified query block. More... | |
| bool | collect_outer_field_processor (uchar *arg) override |
| bool | add_field_to_set_processor (uchar *arg) override |
| Item::walk function. More... | |
| bool | add_field_to_cond_set_processor (uchar *) override |
| Item::walk function. More... | |
| bool | remove_column_from_bitmap (uchar *arg) override |
| Visitor interface for removing all column expressions (Item_field) in this expression tree from a bitmap. More... | |
| bool | find_item_in_field_list_processor (uchar *arg) override |
| Check if an Item_field references some field from a list of fields. More... | |
| bool | find_field_processor (uchar *arg) override |
| Is this an Item_field which references the given Field argument? More... | |
| 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... | |
| bool | mark_field_in_map (uchar *arg) override |
| Mark underlying field in read or write map of a table. More... | |
| bool | used_tables_for_level (uchar *arg) override |
| Return used table information for the specified query block (level). More... | |
| bool | check_column_privileges (uchar *arg) override |
| Check privileges of base table column. More... | |
| bool | check_partition_func_processor (uchar *) override |
| Check if a partition function is allowed. More... | |
| void | bind_fields () override |
| Bind objects from the current execution context to field objects in item trees. More... | |
| bool | is_valid_for_pushdown (uchar *arg) override |
| Check if all the columns present in this expression are from the derived table. More... | |
| bool | check_column_in_window_functions (uchar *arg) override |
| Check if this column is found in PARTITION clause of all the window functions. More... | |
| bool | check_column_in_group_by (uchar *arg) override |
| Check if this column is found in GROUP BY. More... | |
| Item * | replace_with_derived_expr (uchar *arg) override |
| 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... | |
| Item * | replace_with_derived_expr_ref (uchar *arg) override |
| 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... | |
| void | cleanup () override |
| Called for every Item after use (preparation and execution). More... | |
| void | reset_field () |
| Reset all aspect of a field object, so that it can be re-resolved. More... | |
| Item_multi_eq * | find_multi_equality (COND_EQUAL *cond_equal) const |
| Find a field among specified multiple equalities. More... | |
| bool | subst_argument_checker (uchar **arg) override |
| Check whether a field can be substituted by an equal item. More... | |
| Item * | equal_fields_propagator (uchar *arg) override |
| If field matches a multiple equality, set a pointer to that object in the field. More... | |
| Item * | replace_item_field (uchar *) override |
| If this field is the target is the target of replacement, replace it with the info object's item or, if the item is found inside a subquery, the target is an outer reference, so we create a new Item_field, mark it accordingly and replace with that instead. More... | |
| bool | disable_constant_propagation (uchar *) override |
| Item * | replace_equal_field (uchar *) override |
| Replace an Item_field for an equal Item_field that evaluated earlier (if any). More... | |
| uint32 | max_disp_length () |
| Item_field * | field_for_view_update () override |
| bool | fix_outer_field (THD *thd, Field **field, Item_ident **ref_field, bool *complete) |
| Resolve the name of a column that may be an outer reference. More... | |
| Item * | update_value_transformer (uchar *select_arg) override |
| Add the field to the select list and substitute it for the reference to the field. More... | |
| void | print (const THD *thd, String *str, enum_query_type query_type) const override |
| This method is used for to: More... | |
| bool | is_outer_field () const override |
| Field::geometry_type | get_geometry_type () const override |
| const CHARSET_INFO * | charset_for_protocol (void) override |
| void | dbug_print () const |
| 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) override |
| Calculate condition filtering effect for "WHERE field", which implicitly means "WHERE field <> 0". More... | |
| float | get_cond_filter_default_probability (double max_distinct_values, float default_filter) const |
| Returns the probability for the predicate "col OP <val>" to be true for a row in the case where no index statistics or range estimates are available for 'col'. More... | |
| bool | alias_name_used () const override |
| bool | repoint_const_outer_ref (uchar *arg) override |
| If this object is the real_item of an Item_ref, repoint the result_field to field. More... | |
| bool | returns_array () const override |
| Whether the item returns array of its data type. More... | |
| void | set_can_use_prefix_key () override |
| bool | replace_field_processor (uchar *arg) override |
| A processor that replaces any Fields with a Create_field_wrapper. More... | |
| bool | strip_db_table_name_processor (uchar *) override |
| Generated fields don't need db/table names. More... | |
| bool | protected_by_any_value () const |
See m_protected_by_any_value. More... | |
| void | compute_cost (CostOfItem *root_cost) const override |
| Compute the cost of evaluating this Item. More... | |
| 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... | |
| 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 |
| 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 | update_depended_from (uchar *) override |
| 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 | |
| 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 | 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 Field * | make_string_field (TABLE *table) const |
| Create a field to hold a string value from an item. More... | |
| void | quick_fix_field () |
| virtual bool | propagate_type (THD *thd, const Type_properties &type) |
| Propagate data type specifications into parameters and user variables. More... | |
| bool | propagate_type (THD *thd, enum_field_types def=MYSQL_TYPE_VARCHAR, bool pin=false, bool inherit=false) |
| Wrapper for easier calling of propagate_type(const Type_properties &). More... | |
| virtual void | mark_json_as_scalar () |
| For Items with data type JSON, mark that a string argument is treated as a scalar JSON value. More... | |
| virtual std::optional< ContainedSubquery > | get_contained_subquery (const Query_block *outer_query_block) |
| If this item represents a IN/ALL/ANY/comparison_operator subquery, return that (along with data on how it will be executed). More... | |
| type_conversion_status | save_in_field_no_warnings (Field *field, bool no_conversions) |
| Save the item into a field but do not emit any warnings. More... | |
| type_conversion_status | save_in_field (Field *field, bool no_conversions) |
| Save a temporal value in packed longlong format into a Field. More... | |
| void | save_in_field_no_error_check (Field *field, bool no_conversions) |
| A slightly faster value of save_in_field() that returns no error value (you will need to check thd->is_error() yourself), and does not support saving into hidden fields for functional indexes. More... | |
| bool | evaluate (THD *thd, String *str) |
| Evaluate scalar item, possibly using the supplied buffer. More... | |
| const Item * | unwrap_for_eq () const |
| Unwrap an Item argument so that Item::eq() can see the "real" item, and not just the wrapper. 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... | |
| bool | aggregate_type (const char *name, Item **items, uint count) |
| Aggregates data types from array of items into current item. More... | |
| longlong | val_temporal_by_field_type () |
| Return date or time value of item in packed longlong format, depending on item field type. More... | |
| longlong | int_sort_key () |
| Produces a key suitable for filesort. More... | |
| longlong | val_temporal_with_round (enum_field_types type, uint8 dec) |
| Get date or time value in packed longlong format. More... | |
| ulonglong | val_uint () |
| virtual String * | val_str_ascii (String *str) |
| virtual bool | val_bool () |
| bool | error_json () |
| Get the value to return from val_json() in case of errors. More... | |
| bool | get_date_from_non_temporal (MYSQL_TIME *ltime, my_time_flags_t fuzzydate) |
| Convert a non-temporal type to date. More... | |
| bool | get_time_from_non_temporal (MYSQL_TIME *ltime) |
| Convert a non-temporal type to time. More... | |
| my_decimal * | error_decimal (my_decimal *decimal_value) |
| Get the value to return from val_decimal() in case of errors. More... | |
| String * | error_str () |
| Get the value to return from val_str() in case of errors. More... | |
| type_conversion_status | save_time_in_field (Field *field) |
| type_conversion_status | save_date_in_field (Field *field) |
| type_conversion_status | save_str_value_in_field (Field *field, String *result) |
| virtual 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 Item * | clone_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, 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) |
| 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_result_field () const |
| virtual Field * | get_result_field () const |
| virtual bool | is_bool_func () const |
| virtual void | no_rows_in_result () |
| virtual Item * | copy_or_same (THD *) |
| virtual Item * | copy_andor_structure (THD *) |
| virtual Item * | real_item () |
| virtual const Item * | real_item () const |
| virtual const CHARSET_INFO * | compare_collation () const |
| virtual bool | walk (Item_processor processor, enum_walk walk, uchar *arg) |
| Traverses a tree of Items in prefix and/or postfix order. More... | |
| template<class T > | |
| auto | walk_helper_thunk (uchar *arg) |
| template<class T > | |
| auto | analyze_helper_thunk (uchar **arg) |
| See CompileItem. More... | |
| virtual Item * | transform (Item_transformer transformer, uchar *arg) |
| Perform a generic transformation of the Item tree, by adding zero or more additional Item objects to it. More... | |
| virtual Item * | compile (Item_analyzer analyzer, uchar **arg_p, Item_transformer transformer, uchar *arg_t) |
| Perform a generic "compilation" of the Item tree, ie transform the Item tree by adding zero or more Item objects to it. More... | |
| virtual void | traverse_cond (Cond_traverser traverser, void *arg, traverse_order) |
| virtual bool | intro_version (uchar *) |
| bool | cleanup_processor (uchar *) |
| cleanup() item if it is resolved ('fixed'). More... | |
| virtual bool | visitor_processor (uchar *arg) |
| A processor to handle the select lex visitor framework. More... | |
| virtual bool | find_item_processor (uchar *arg) |
| virtual bool | is_non_const_over_literals (uchar *) |
| virtual bool | cast_incompatible_args (uchar *) |
| Wrap incompatible arguments in CAST nodes to the expected data types. More... | |
| virtual bool | reset_wf_state (uchar *arg) |
| Reset execution state for such window function types as determined by arg. More... | |
| virtual bool | inform_item_in_cond_of_tab (uchar *) |
| virtual bool | clean_up_after_removal (uchar *arg) |
| Clean up after removing the item from the item tree. 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... | |
| Item * | cache_const_expr_transformer (uchar *item) |
| Cache item if needed. More... | |
| virtual bool | equality_substitution_analyzer (uchar **) |
| virtual Item * | equality_substitution_transformer (uchar *) |
| virtual bool | explain_subquery_checker (uchar **) |
| virtual Item * | explain_subquery_propagator (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 Item * | replace_view_refs_with_clone (uchar *arg) |
| Assuming this expression is part of a condition that would be pushed to a materialized derived table, replace, in this expression, each view reference with a clone of the expression in merged derived table's definition. More... | |
| virtual Item * | this_item () |
| virtual const Item * | this_item () const |
| virtual Item ** | this_item_addr (THD *, Item **addr_arg) |
| virtual uint | cols () const |
| virtual Item * | element_index (uint) |
| virtual Item ** | addr (uint) |
| virtual bool | check_cols (uint c) |
| virtual bool | null_inside () |
| virtual void | bring_value () |
| Field * | tmp_table_field_from_field_type (TABLE *table, bool fixed_length) const |
| Create a field based on field_type of argument. More... | |
| virtual Item * | truth_transformer (THD *thd, Bool_test test) |
| Informs an item that it is wrapped in a truth test, in case it wants to transforms itself to implement this test by itself. More... | |
| virtual Item * | replace_scalar_subquery (uchar *) |
| When walking the item tree seeing an Item_singlerow_subselect matching a target, replace it with a substitute field used when transforming scalar subqueries into derived tables. More... | |
| virtual Item * | replace_func_call (uchar *) |
| virtual Item * | replace_item_view_ref (uchar *) |
| virtual Item * | replace_aggregate (uchar *) |
| virtual Item * | replace_outer_ref (uchar *) |
| virtual bool | update_aggr_refs (uchar *) |
| A walker processor overridden by Item_aggregate_ref, q.v. More... | |
| Item * | convert_charset (THD *thd, const CHARSET_INFO *tocs, bool ignore_errors=false) |
| Convert constant string in this object into the specified character set. More... | |
| void | delete_self () |
| Delete this item. More... | |
| virtual bool | is_splocal () const |
| virtual Settable_routine_parameter * | get_settable_routine_parameter () |
| bool | is_temporal_with_date () const |
| bool | is_temporal_with_date_and_time () const |
| bool | is_temporal_with_time () const |
| bool | is_temporal () const |
| bool | has_compatible_context (Item *item) const |
| Check whether this and the given item has compatible comparison context. More... | |
| String * | check_well_formed_result (String *str, bool send_error, bool truncate) |
| Verifies that the input string is well-formed according to its character set. More... | |
| bool | eq_by_collation (Item *item, 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) |
| 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 Item * | gc_subst_transformer (uchar *) |
| Transformer function for GC substitution. 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... | |
| 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... | |
| 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 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_field | super |
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 | |
| static void * | operator new (size_t size) noexcept |
| static void * | operator new (size_t size, MEM_ROOT *mem_root, const std::nothrow_t &arg=std::nothrow) noexcept |
| static void | operator delete (void *ptr, size_t size) |
| static void | operator delete (void *, MEM_ROOT *, const std::nothrow_t &) noexcept |
| static enum_field_types | result_to_type (Item_result result) |
| static Item_result | type_to_result (enum_field_types type) |
| static enum_field_types | type_for_variable (enum_field_types src_type) |
| Provide data type for a user or system variable, based on the type of the item that is assigned to the variable. More... | |
| static enum_field_types | string_field_type (uint32 max_bytes) |
| Determine correct string field type, based on string length. More... | |
| static const CHARSET_INFO * | default_charset () |
| Static Public Member Functions inherited from Parse_tree_node_tmpl< Context > | |
| static void * | operator new (size_t size, MEM_ROOT *mem_root, const std::nothrow_t &arg=std::nothrow) noexcept |
| static void | operator delete (void *ptr, size_t size) |
| static void | operator delete (void *, MEM_ROOT *, const std::nothrow_t &) noexcept |
| Public Attributes inherited from Item_field | |
| Field * | field {nullptr} |
| Source field. More... | |
| uint16 | field_index {NO_FIELD_INDEX} |
| Index for this field in table->field array. More... | |
| Item_multi_eq * | item_equal_all_join_nests {nullptr} |
| bool | no_constant_propagation {false} |
| If true, the optimizer's constant propagation will not replace this item with an equal constant. More... | |
| Access_bitmask | have_privileges {0} |
| bool | any_privileges {false} |
| bool | can_use_prefix_key {false} |
| Public Attributes inherited from Item_ident | |
| Name_resolution_context * | context |
| 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_ref * | m_table_ref {nullptr} |
| Points to the Table_ref object of the table or view that the column or reference is resolved against (only valid after resolving). More... | |
| Query_block * | depended_from {nullptr} |
| For a column or reference that is an outer reference, depended_from points to the qualifying query block, otherwise it is NULL (only valid after resolving). More... | |
| Public Attributes inherited from Item | |
| Item * | next_free |
| Intrusive list pointer for free list. More... | |
| DTCollation | collation |
| Character set and collation properties assigned for this Item. More... | |
| Item_name_string | item_name |
| Name from query. More... | |
| Item_name_string | orig_name |
| Original item name (if it was renamed) More... | |
| uint32 | max_length |
| Maximum length of result of evaluating this item, in number of bytes. More... | |
| item_marker | marker |
| This member has several successive meanings, depending on the phase we're in (. More... | |
| Item_result | cmp_context |
| Comparison context. More... | |
| bool | fixed |
| True if item has been resolved. More... | |
| uint8 | decimals |
| Number of decimals in result when evaluating this item. More... | |
| bool | null_value |
| True if item is null. More... | |
| bool | unsigned_flag |
| bool | m_is_window_function |
| True if item represents window func. More... | |
| bool | hidden {false} |
| If the item is in a SELECT list (Query_block::fields) and hidden is true, the item wasn't actually in the list as given by the user (it was added by the optimizer, to e.g. More... | |
| bool | m_in_check_constraint_exec_ctx {false} |
| True if item is a top most element in the expression being evaluated for a check constraint. More... | |
| Public Attributes inherited from Parse_tree_node_tmpl< Context > | |
| POS | m_pos |
| Protected Member Functions inherited from Item_field | |
| void | set_field (Field *field) |
| void | fix_after_pullout (Query_block *parent_query_block, Query_block *removed_query_block) override |
| Fix after tables have been moved from one query_block level to the parent level, e.g by semijoin conversion. More... | |
| 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 | |
| String * | make_empty_result () |
| Sets the result value of the function an empty string, using the current character set. More... | |
| bool | skip_itemize (Item **res) |
| Helper function to skip itemize() for grammar-allocated items. More... | |
| String * | val_string_from_real (String *str) |
| String * | val_string_from_int (String *str) |
| String * | val_string_from_decimal (String *str) |
| String * | val_string_from_date (String *str) |
| String * | val_string_from_datetime (String *str) |
| String * | val_string_from_time (String *str) |
| my_decimal * | val_decimal_from_real (my_decimal *decimal_value) |
| my_decimal * | val_decimal_from_int (my_decimal *decimal_value) |
| my_decimal * | val_decimal_from_string (my_decimal *decimal_value) |
| my_decimal * | val_decimal_from_date (my_decimal *decimal_value) |
| my_decimal * | val_decimal_from_time (my_decimal *decimal_value) |
| longlong | val_int_from_decimal () |
| longlong | val_int_from_date () |
| longlong | val_int_from_time () |
| longlong | val_int_from_datetime () |
| longlong | val_int_from_string () |
| double | val_real_from_decimal () |
| double | val_real_from_string () |
| bool | error_bool () |
| Get the value to return from val_bool() in case of errors. More... | |
| int | error_int () |
| Get the value to return from val_int() in case of errors. More... | |
| double | error_real () |
| Get the value to return from val_real() in case of errors. More... | |
| bool | error_date () |
| Get the value to return from get_date() in case of errors. More... | |
| bool | error_time () |
| Get the value to return from get_time() in case of errors. More... | |
| String * | null_return_str () |
| Gets the value to return from val_str() when returning a NULL value. More... | |
| bool | get_date_from_string (MYSQL_TIME *ltime, my_time_flags_t flags) |
| Convert val_str() to date in MYSQL_TIME. More... | |
| bool | get_date_from_real (MYSQL_TIME *ltime, my_time_flags_t flags) |
| Convert val_real() to date in MYSQL_TIME. More... | |
| bool | get_date_from_decimal (MYSQL_TIME *ltime, my_time_flags_t flags) |
| Convert val_decimal() to date in MYSQL_TIME. More... | |
| bool | get_date_from_int (MYSQL_TIME *ltime, my_time_flags_t flags) |
| Convert val_int() to date in MYSQL_TIME. More... | |
| bool | get_date_from_time (MYSQL_TIME *ltime) |
| Convert get_time() from time to date in MYSQL_TIME. More... | |
| bool | get_date_from_numeric (MYSQL_TIME *ltime, my_time_flags_t fuzzydate) |
| Convert a numeric type to date. More... | |
| bool | get_time_from_string (MYSQL_TIME *ltime) |
| Convert val_str() to time in MYSQL_TIME. More... | |
| bool | get_time_from_real (MYSQL_TIME *ltime) |
| Convert val_real() to time in MYSQL_TIME. More... | |
| bool | get_time_from_decimal (MYSQL_TIME *ltime) |
| Convert val_decimal() to time in MYSQL_TIME. More... | |
| bool | get_time_from_int (MYSQL_TIME *ltime) |
| Convert val_int() to time in MYSQL_TIME. More... | |
| bool | get_time_from_date (MYSQL_TIME *ltime) |
| Convert date to time. More... | |
| bool | get_time_from_datetime (MYSQL_TIME *ltime) |
| Convert datetime to time. More... | |
| bool | get_time_from_numeric (MYSQL_TIME *ltime) |
| Convert a numeric type to time. More... | |
| 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_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_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... | |
Represents [schema.
][table.]* in a select list
Item_asterisk is used to insert placeholder objects for the special select list item * (asterisk) into AST. Those placeholder objects are to be substituted later with e.g. a list of real table columns by a resolver (
|
private |
|
inline |
Constructor.
| pos | Location of the * (asterisk) lexeme. |
| opt_schema_name | Schema name or nullptr. |
| opt_table_name | Table name or nullptr. |
|
overridevirtual |
The core function that does the actual itemization.
itemize() is just a wrapper over this.
Reimplemented from Item_field.
Resolve the name of a column reference.
The method resolves the column reference represented by 'this' as a column present in one of: FROM clause, SELECT clause, GROUP BY clause of a query Q, or in outer queries that contain Q.
The name resolution algorithm used is (where [T_j] is an optional table name that qualifies the column name):
Notice that compared to Item_ref::fix_fields, here we first search the FROM clause, and then we search the SELECT and GROUP BY clauses.
For the case where a table reference is already set for the field, we just need to make a call to set_field(). This is true for a cloned field used during condition pushdown to derived tables. A cloned field inherits table reference, depended_from, context and field from the original field. set_field() ensures all other members are set correctly.
| [in] | thd | current thread |
| [in,out] | reference | view column if this item was resolved to a view column |
Reimplemented from Item_field.
|
inlineoverridevirtual |
Checks if the current object represents an asterisk select list item.
Reimplemented from Item_field.
1.9.2