MySQL 8.3.0
Source Code Documentation
opt_explain_traditional.h
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22
23#ifndef OPT_EXPLAIN_FORMAT_TRADITIONAL_INCLUDED
24#define OPT_EXPLAIN_FORMAT_TRADITIONAL_INCLUDED
25
26#include <assert.h>
27// assert
28#include <memory>
29#include <string>
30#include <vector>
31
34
35class Item;
36class Json_dom;
37class Json_object;
38class Query_result;
40template <class T>
41class mem_root_deque;
42
43/**
44 Formatter for the traditional EXPLAIN output
45*/
46
48 class Item_null *nil;
49 qep_row column_buffer; ///< buffer for the current output row
50
51 public:
53
54 bool is_hierarchical() const override { return false; }
55 bool send_headers(Query_result *result) override;
57 const Explain_format_flags *) override {
58 return false;
59 }
60 bool end_context(enum_parsing_context) override { return false; }
61 bool flush_entry() override;
62 qep_row *entry() override { return &column_buffer; }
63
64 private:
66};
67
69 public:
71
72 bool is_hierarchical() const override { return false; }
73 bool send_headers(Query_result *) override {
74 assert(false);
75 return true;
76 }
78 const Explain_format_flags *) override {
79 assert(false);
80 return true;
81 }
83 assert(false);
84 return true;
85 }
86 bool flush_entry() override {
87 assert(false);
88 return true;
89 }
90 qep_row *entry() override {
91 assert(false);
92 return nullptr;
93 }
94 bool is_iterator_based() const override { return true; }
95
96 /* Convert Json object to string */
97 std::string ExplainJsonToString(Json_object *json) override;
98 void ExplainPrintTreeNode(const Json_dom *json, int level,
99 std::string *explain,
100 std::vector<std::string> *tokens_for_force_subplan);
101
102 private:
104
105 void AppendChildren(const Json_dom *children, int level, std::string *explain,
106 std::vector<std::string> *tokens_for_force_subplan,
107 std::string *child_token_digest);
108 void ExplainPrintCosts(const Json_object *obj, std::string *explain);
109};
110
111#endif // OPT_EXPLAIN_FORMAT_TRADITIONAL_INCLUDED
Kerberos Client Authentication nullptr
Definition: auth_kerberos_client_plugin.cc:250
Definition: opt_explain_format.h:450
Formatter for the traditional EXPLAIN output.
Definition: opt_explain_traditional.h:47
bool flush_entry() override
Flush TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.cc:216
qep_row column_buffer
buffer for the current output row
Definition: opt_explain_traditional.h:49
Explain_format_traditional()
Definition: opt_explain_traditional.h:52
class Item_null * nil
Definition: opt_explain_traditional.h:48
bool begin_context(enum_parsing_context, Query_expression *, const Explain_format_flags *) override
Enter a specified context.
Definition: opt_explain_traditional.h:56
qep_row * entry() override
Get a pointer to the current TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.h:62
bool is_hierarchical() const override
A hierarchical text or a plain table.
Definition: opt_explain_traditional.h:54
bool send_headers(Query_result *result) override
Send EXPLAIN header item(s) to output stream.
Definition: opt_explain_traditional.cc:87
bool push_select_type(mem_root_deque< Item * > *items)
Definition: opt_explain_traditional.cc:178
bool end_context(enum_parsing_context) override
Leave the current context.
Definition: opt_explain_traditional.h:60
Definition: opt_explain_traditional.h:68
std::string ExplainJsonToString(Json_object *json) override
Convert Json object to string.
Definition: explain_access_path.cc:2038
bool end_context(enum_parsing_context) override
Leave the current context.
Definition: opt_explain_traditional.h:82
bool send_headers(Query_result *) override
Send EXPLAIN header item(s) to output stream.
Definition: opt_explain_traditional.h:73
bool push_select_type(mem_root_deque< Item * > *items)
bool flush_entry() override
Flush TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.h:86
qep_row * entry() override
Get a pointer to the current TABLE/JOIN_TAB property set.
Definition: opt_explain_traditional.h:90
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:2274
void ExplainPrintTreeNode(const Json_dom *json, int level, std::string *explain, std::vector< std::string > *tokens_for_force_subplan)
Definition: explain_access_path.cc:2062
Explain_format_tree()=default
bool is_hierarchical() const override
A hierarchical text or a plain table.
Definition: opt_explain_traditional.h:72
void ExplainPrintCosts(const Json_object *obj, std::string *explain)
Definition: explain_access_path.cc:2218
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:94
bool begin_context(enum_parsing_context, Query_expression *, const Explain_format_flags *) override
Enter a specified context.
Definition: opt_explain_traditional.h:77
Base class for structured and hierarchical EXPLAIN output formatters.
Definition: opt_explain_format.h:505
Definition: item.h:4702
Base class that is used to represent any kind of expression in a relational query.
Definition: item.h:933
JSON DOM abstract base class.
Definition: json_dom.h:171
Represents a JSON container value of type "object" (ECMA), type J_OBJECT here.
Definition: json_dom.h:367
This class represents a query expression (one query block or several query blocks combined with UNION...
Definition: sql_lex.h:624
Definition: query_result.h:57
A (partial) implementation of std::deque allocating its blocks on a MEM_ROOT.
Definition: mem_root_deque.h:110
Helper class for table property buffering.
Definition: opt_explain_format.h:149
EXPLAIN FORMAT=<format> <command>.
enum_parsing_context
Names for different query parse tree parts.
Definition: parse_tree_node_base.h:60
Definition: result.h:29