Node class to wrap a subquery node tree. More...

Inheritance diagram for opt_explain_json_namespace::subquery_ctx:

Public Member Functions
	subquery_ctx (enum_parsing_context type_arg, const char name_arg, context parent_arg)

qep_row *	entry () override

bool	cacheable () override

bool	dependent () override

bool	format (Opt_trace_context *json) override
	Pass the node with its child nodes to a JSON formatter. More...

void	set_child (context *child) override
	Associate a child node with this node. More...

size_t	id (bool hide) override
	Analogue of the "id" column in the traditional EXPLAIN output. More...

Public Member Functions inherited from opt_explain_json_namespace::context
	context (enum_parsing_context type_arg, const char name_arg, context parent_arg)

virtual	~context ()=default

bool	is_query_block () const

virtual enum_mod_type	get_mod_type ()

virtual void	set_setop_result (setop_result_ctx *)
	associate CTX_UNION_RESULT node with CTX_UNION node More...

virtual bool	add_subquery (subquery_list_enum subquery_type, subquery_ctx *ctx)
	Append a subquery node to the specified list of the unit node. More...

virtual bool	format_nested_loop (Opt_trace_context *json)
	Format nested loop join subtree (if any) to JSON formatter. More...

virtual bool	add_join_tab (joinable_ctx *ctx)
	Add a CTX_QEP_TAB node to a CTX_JOIN node. More...

virtual void	set_sort (sort_ctx *ctx)
	Set nested ORDER BY/GROUP BY/DISTINCT node to `ctx`. More...

virtual void	set_window (window_ctx *ctx)
	Set nested WINDOW node to `ctx`. More...

virtual bool	add_query_spec (context *ctx)
	Add a query specification node to the CTX_UNION node. More...

virtual bool	find_and_set_derived (context *subquery)
	Try to associate a derived subquery node with this or underlying node. More...

virtual int	add_where_subquery (subquery_ctx ctx, Query_expression subquery)
	Associate WHERE subqueries of given context and unit with this object. More...

virtual bool	format_derived (Opt_trace_context *)
	Helper function to format output for derived subquery if any. More...

virtual bool	format_where (Opt_trace_context *)
	Helper function to format output for associated WHERE subqueries if any. More...

virtual bool	format_query_expression (Opt_trace_context *)
	Helper function to format output for HAVING, ORDER/GROUP BY subqueries. More...

Public Member Functions inherited from Explain_context
	Explain_context (enum_parsing_context type_arg)

Public Member Functions inherited from qep_row
	qep_row ()

virtual	~qep_row ()=default

void	cleanup ()

virtual void	register_where_subquery (Query_expression *subquery)
	Remember a subquery's unit. More...

void	format_extra (Opt_trace_object *obj)

Private Member Functions
bool	format_body (Opt_trace_context json, Opt_trace_object obj) override
	Format JSON object body. More...

bool	format_query_block (Opt_trace_context *json)

Private Attributes
context *	subquery
	hosted subquery tree: CTX_JOIN, CTX_UNION, CTX_INTERSECT, CTX_EXCEPT or CTX_UNARY More...

Additional Inherited Members
Public Attributes inherited from opt_explain_json_namespace::context
context *	parent
	link to parent node or NULL More...

Public Attributes inherited from Explain_context
enum_parsing_context	type
	type tag More...

Public Attributes inherited from qep_row
column< uint >	col_id
	"id" column: seq. number of SELECT within the query More...

column< enum_explain_type >	col_select_type
	"select_type" column More...

mem_root_str	col_table_name
	"table" to which the row of output refers More...

List< const char >	col_partitions
	"partitions" column More...

mem_root_str	col_join_type
	"type" column, see join_type_str array More...

List< const char >	col_possible_keys
	"possible_keys": comma-separated list More...

mem_root_str	col_key
	"key" column: index that is actually decided to use More...

mem_root_str	col_key_len
	"key_length" column: length of the "key" above More...

List< const char >	col_ref
	"ref":columns/constants which are compared to "key" More...

column< float >	col_filtered
	"filtered": % of rows filtered by condition More...

List< extra >	col_extra
	"extra" column (traditional) or property list More...

mem_root_str	col_message
	replaces "Extra" column if not empty More...

mem_root_str	col_attached_condition
	former "Using where" More...

column< ulonglong >	col_rows
	"rows": estimated number of examined table rows per single scan More...

column< ulonglong >	col_prefix_rows
	"rows": estimated number of examined table rows per query More...

column< double >	col_read_cost
	Time to read the table. More...

column< double >	col_prefix_cost
	Cost of the partial join including this table. More...

column< double >	col_cond_cost
	Cost of evaluating conditions on this table per query. More...

mem_root_str	col_data_size_query
	Size of data expected to be read per query. More...

List< const char >	col_used_columns
	List of used columns. More...

List< const char >	col_partial_update_columns
	List of columns that can be updated using partial update. More...

uint	query_block_id
	query block id for materialized subqueries More...

List< opt_explain_json_namespace::context >	derived_from
	List of "derived" subquery trees. More...

List< const char >	col_key_parts
	used parts of the key More...

bool	is_dependent

bool	is_cacheable

bool	using_temporary

enum_mod_type	mod_type

bool	is_materialized_from_subquery

uint	derived_clone_id
	If a clone of a materialized derived table, this is the ID of the first underlying query block of the first materialized derived table. More...

List< Window > *	m_windows
	Windows to describe in this node. More...

Protected Attributes inherited from opt_explain_json_namespace::context
const char *	name

Detailed Description

Node class to wrap a subquery node tree.

Implements CTX_WHERE, CTX_HAVING, CTX_ORDER_BY_SQ, CTX_GROUP_BY_SQ and CTX_OPTIMIZED_AWAY_SUBQUERY context nodes. This class hosts underlying join_ctx or uion_ctx.

Is used for a subquery, a derived table.

Constructor & Destructor Documentation

◆ subquery_ctx()

opt_explain_json_namespace::subquery_ctx::subquery_ctx	(	enum_parsing_context	type_arg,
		const char *	name_arg,
		context *	parent_arg
	)

inline

Member Function Documentation

◆ cacheable()

bool opt_explain_json_namespace::subquery_ctx::cacheable ( )

inlineoverridevirtual

Reimplemented from opt_explain_json_namespace::context.

◆ dependent()

bool opt_explain_json_namespace::subquery_ctx::dependent ( )

inlineoverridevirtual

Reimplemented from opt_explain_json_namespace::context.

◆ entry()

qep_row * opt_explain_json_namespace::subquery_ctx::entry ( )

inlineoverridevirtual

Reimplemented from opt_explain_json_namespace::context.

◆ format()

bool opt_explain_json_namespace::subquery_ctx::format ( Opt_trace_context * json )

inlineoverridevirtual

Pass the node with its child nodes to a JSON formatter.

Parameters

json Formatter

Return values

false	Ok
true	Error

Note: The join_ctx class overloads this function.

Reimplemented from opt_explain_json_namespace::context.

◆ format_body()

bool opt_explain_json_namespace::subquery_ctx::format_body	(	Opt_trace_context *	json,
		Opt_trace_object *	obj
	)

inlineoverrideprivatevirtual

Format JSON object body.

Parameters

json	Formatter
obj	Object of this body

Return values

false	Ok
true	Error

Implements opt_explain_json_namespace::context.

◆ format_query_block()

bool opt_explain_json_namespace::subquery_ctx::format_query_block ( Opt_trace_context * json )

inlineprivate

◆ id()

size_t opt_explain_json_namespace::subquery_ctx::id ( bool hide )

inlineoverridevirtual

Analogue of the "id" column in the traditional EXPLAIN output.

Parameters

hide	if true, ban the output of K_SELECT_ID JSON property in the underlying table_with_where_and_derived_ctx objects

Returns: "Select number" that is associated with this node

Implements opt_explain_json_namespace::context.

◆ set_child()

void opt_explain_json_namespace::subquery_ctx::set_child ( context * )

inlineoverridevirtual

Associate a child node with this node.

This function is to be overloaded by subquery_ctx.

Reimplemented from opt_explain_json_namespace::context.

Member Data Documentation

◆ subquery

context* opt_explain_json_namespace::subquery_ctx::subquery

private

hosted subquery tree: CTX_JOIN, CTX_UNION, CTX_INTERSECT, CTX_EXCEPT or CTX_UNARY

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

sql/opt_explain_json.cc

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ subquery_ctx()

Member Function Documentation

◆ cacheable()

◆ dependent()

◆ entry()

◆ format()

◆ format_body()

◆ format_query_block()

◆ id()

◆ set_child()

Member Data Documentation

◆ subquery