MySQL 8.4.3
Source Code Documentation
opt_explain_traditional.h
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23
24#ifndef OPT_EXPLAIN_FORMAT_TRADITIONAL_INCLUDED
25#define OPT_EXPLAIN_FORMAT_TRADITIONAL_INCLUDED
26
27#include <assert.h>
28// assert
29#include <memory>
30#include <string>
31#include <vector>
32
35
36class Item;
37class Json_dom;
38class Json_object;
39class Query_result;
41template <class T>
42class mem_root_deque;
43
44/**
45 Formatter for the traditional EXPLAIN output
46*/
47
49 class Item_null *nil;
50 qep_row column_buffer; ///< buffer for the current output row
51
52 public:
54
55 bool is_hierarchical() const override { return false; }
56 bool send_headers(Query_result *result) override;
58 const Explain_format_flags *) override {
59 return false;
60 }
61 bool end_context(enum_parsing_context) override { return false; }
62 bool flush_entry() override;
63 qep_row *entry() override { return &column_buffer; }
64
65 private:
67};
68
70 public:
72
73 bool is_hierarchical() const override { return false; }
74 bool send_headers(Query_result *) override {
75 assert(false);
76 return true;
77 }
79 const Explain_format_flags *) override {
80 assert(false);
81 return true;
82 }
84 assert(false);
85 return true;
86 }
87 bool flush_entry() override {
88 assert(false);
89 return true;
90 }
91 qep_row *entry() override {
92 assert(false);
93 return nullptr;
94 }
95 bool is_iterator_based() const override { return true; }
96
97 /* Convert Json object to string */
98 std::string ExplainJsonToString(Json_object *json) override;
99 void ExplainPrintTreeNode(const Json_dom *json, int level,
100 std::string *explain,
101 std::vector<std::string> *tokens_for_force_subplan);
102
103 private:
105
106 void AppendChildren(const Json_dom *children, int level, std::string *explain,
107 std::vector<std::string> *tokens_for_force_subplan,
108 std::string *child_token_digest);
109 void ExplainPrintCosts(const Json_object *obj, std::string *explain);
110};
111
112#endif // OPT_EXPLAIN_FORMAT_TRADITIONAL_INCLUDED
Kerberos Client Authentication nullptr
Definition: auth_kerberos_client_plugin.cc:251
Definition: opt_explain_format.h:451
Formatter for the traditional EXPLAIN output.
Definition: opt_explain_traditional.h:48
bool flush_entry() override
Flush TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.cc:217
qep_row column_buffer
buffer for the current output row
Definition: opt_explain_traditional.h:50
Explain_format_traditional()
Definition: opt_explain_traditional.h:53
class Item_null * nil
Definition: opt_explain_traditional.h:49
bool begin_context(enum_parsing_context, Query_expression *, const Explain_format_flags *) override
Enter a specified context.
Definition: opt_explain_traditional.h:57
qep_row * entry() override
Get a pointer to the current TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.h:63
bool is_hierarchical() const override
A hierarchical text or a plain table.
Definition: opt_explain_traditional.h:55
bool send_headers(Query_result *result) override
Send EXPLAIN header item(s) to output stream.
Definition: opt_explain_traditional.cc:88
bool push_select_type(mem_root_deque< Item * > *items)
Definition: opt_explain_traditional.cc:179
bool end_context(enum_parsing_context) override
Leave the current context.
Definition: opt_explain_traditional.h:61
Definition: opt_explain_traditional.h:69
std::string ExplainJsonToString(Json_object *json) override
Convert Json object to string.
Definition: explain_access_path.cc:2081
bool end_context(enum_parsing_context) override
Leave the current context.
Definition: opt_explain_traditional.h:83
bool send_headers(Query_result *) override
Send EXPLAIN header item(s) to output stream.
Definition: opt_explain_traditional.h:74
bool push_select_type(mem_root_deque< Item * > *items)
bool flush_entry() override
Flush TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.h:87
qep_row * entry() override
Get a pointer to the current TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.h:91
void AppendChildren(const Json_dom *children, int level, std::string *explain, std::vector< std::string > *tokens_for_force_subplan, std::string *child_token_digest)
Definition: explain_access_path.cc:2201
void ExplainPrintTreeNode(const Json_dom *json, int level, std::string *explain, std::vector< std::string > *tokens_for_force_subplan)
Definition: explain_access_path.cc:2105
Explain_format_tree()=default
bool is_hierarchical() const override
A hierarchical text or a plain table.
Definition: opt_explain_traditional.h:73
void ExplainPrintCosts(const Json_object *obj, std::string *explain)
Definition: explain_access_path.cc:2144
bool is_iterator_based() const override
Whether the format closely resembles the final plan to be executed by execution iterators (See RowIte...
Definition: opt_explain_traditional.h:95
bool begin_context(enum_parsing_context, Query_expression *, const Explain_format_flags *) override
Enter a specified context.
Definition: opt_explain_traditional.h:78
Base class for structured and hierarchical EXPLAIN output formatters.
Definition: opt_explain_format.h:506
Definition: item.h:4704
Base class that is used to represent any kind of expression in a relational query.
Definition: item.h:936
JSON DOM abstract base class.
Definition: json_dom.h:173
Represents a JSON container value of type "object" (ECMA), type J_OBJECT here.
Definition: json_dom.h:369
This class represents a query expression (one query block or several query blocks combined with UNION...
Definition: sql_lex.h:626
Definition: query_result.h:58
A (partial) implementation of std::deque allocating its blocks on a MEM_ROOT.
Definition: mem_root_deque.h:111
Helper class for table property buffering.
Definition: opt_explain_format.h:150
EXPLAIN FORMAT=<format> <command>.
enum_parsing_context
Names for different query parse tree parts.
Definition: parse_tree_node_base.h:61
Definition: result.h:30