MySQL  8.0.21
Source Code Documentation
opt_explain_json_namespace::join_ctx Class Reference

Node class for the CTX_JOIN context. More...

Inheritance diagram for opt_explain_json_namespace::join_ctx:
opt_explain_json_namespace::unit_ctx qep_row opt_explain_json_namespace::context Explain_context opt_explain_json_namespace::duplication_weedout_ctx opt_explain_json_namespace::materialize_ctx opt_explain_json_namespace::sort_ctx opt_explain_json_namespace::window_ctx opt_explain_json_namespace::sort_with_subqueries_ctx

Public Member Functions

 join_ctx (enum_parsing_context type_arg, const char *name_arg, context *parent_arg)
 
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 qep_rowentry ()
 
virtual bool find_and_set_derived (context *subquery)
 Associate a CTX_DERIVED node with its CTX_QEP_TAB 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 size_t id (bool hide)
 Analogue of the "id" column in the traditional EXPLAIN output. More...
 
virtual bool cacheable ()
 
virtual bool dependent ()
 
virtual int add_where_subquery (subquery_ctx *ctx, SELECT_LEX_UNIT *subquery)
 Associate WHERE subqueries of given context and unit with this object. More...
 
- Public Member Functions inherited from opt_explain_json_namespace::unit_ctx
 unit_ctx (enum_parsing_context type_arg, const char *name_arg, context *parent_arg)
 
bool has_no_subqueries () const
 Helper function to distinguish subquery-less nodes. More...
 
virtual bool format_unit (Opt_trace_context *json)
 Helper function to format output for HAVING, ORDER/GROUP BY subqueries. 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 ()
 
virtual bool format (Opt_trace_context *json)
 Pass the node with its child nodes to a JSON formatter. More...
 
bool is_query_block () const
 
virtual enum_mod_type get_mod_type ()
 
virtual void set_child (context *)
 Associate a child node with this node. More...
 
virtual void set_union_result (union_result_ctx *)
 associate CTX_UNION_RESULT node with CTX_UNION node More...
 
virtual bool add_query_spec (context *ctx)
 Add a query specification node to the CTX_UNION node. 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...
 
- 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 ()
 
void cleanup ()
 
virtual void register_where_subquery (SELECT_LEX_UNIT *subquery)
 Remember a subquery's unit. More...
 
void format_extra (Opt_trace_object *obj)
 

Protected Member Functions

virtual bool format_body (Opt_trace_context *json, Opt_trace_object *obj)
 Format JSON object body. More...
 
bool format_body_inner (Opt_trace_context *json, Opt_trace_object *obj)
 
virtual const char * get_cost_tag ()
 

Protected Attributes

List< joinable_ctxjoin_tabs
 hosted JOIN_TAB nodes More...
 
sort_ctxsort
 
window_ctxwindow
 
- Protected Attributes inherited from opt_explain_json_namespace::context
const char * name
 

Additional Inherited Members

- Public Attributes inherited from opt_explain_json_namespace::context
contextparent
 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< uintcol_id
 "id" column: seq. number of SELECT withing the query More...
 
column< enum_explain_typecol_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< extracol_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< ulonglongcol_rows
 "rows": estimated number of examined table rows per single scan More...
 
column< ulonglongcol_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::contextderived_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...
 

Detailed Description

Node class for the CTX_JOIN context.

Constructor & Destructor Documentation

◆ join_ctx()

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

Member Function Documentation

◆ add_join_tab()

virtual bool opt_explain_json_namespace::join_ctx::add_join_tab ( joinable_ctx ctx)
inlinevirtual

Add a CTX_QEP_TAB node to a CTX_JOIN node.

Parameters
ctxCTX_QEP_TAB node
Return values
falseOk
trueError

Reimplemented from opt_explain_json_namespace::context.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

◆ add_subquery()

bool opt_explain_json_namespace::join_ctx::add_subquery ( subquery_list_enum  subquery_type,
subquery_ctx ctx 
)
virtual

Append a subquery node to the specified list of the unit node.

Parameters
subquery_typeDescribes the Item tree where the subquery exists
ctxSubquery node
Return values
falseOk
trueError

Reimplemented from opt_explain_json_namespace::unit_ctx.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, opt_explain_json_namespace::materialize_ctx, and opt_explain_json_namespace::sort_with_subqueries_ctx.

◆ add_where_subquery()

int opt_explain_json_namespace::join_ctx::add_where_subquery ( subquery_ctx ctx,
SELECT_LEX_UNIT subquery 
)
virtual

Associate WHERE subqueries of given context and unit with this object.

Parameters
ctxContext of WHERE subquery
subqueryFor CTX_QEP_TAB: match given unit with a previously collected by the register_where_subquery function.
Returns
-1 subquery wasn't found 0 subqusery were added 1 error occurred

Reimplemented from opt_explain_json_namespace::context.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

◆ cacheable()

bool opt_explain_json_namespace::join_ctx::cacheable ( )
virtual

◆ dependent()

bool opt_explain_json_namespace::join_ctx::dependent ( )
virtual

◆ entry()

virtual qep_row* opt_explain_json_namespace::join_ctx::entry ( )
inlinevirtual

◆ find_and_set_derived()

bool opt_explain_json_namespace::join_ctx::find_and_set_derived ( context subquery)
virtual

Associate a CTX_DERIVED node with its CTX_QEP_TAB node.

Parameters
subqueryderived subquery tree

Reimplemented from opt_explain_json_namespace::context.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

◆ format_body()

bool opt_explain_json_namespace::join_ctx::format_body ( Opt_trace_context json,
Opt_trace_object obj 
)
protectedvirtual

◆ format_body_inner()

bool opt_explain_json_namespace::join_ctx::format_body_inner ( Opt_trace_context json,
Opt_trace_object obj 
)
protected

◆ format_nested_loop()

bool opt_explain_json_namespace::join_ctx::format_nested_loop ( Opt_trace_context json)
virtual

Format nested loop join subtree (if any) to JSON formatter.

Parameters
jsonFormatter
Return values
falseOk
trueError

Reimplemented from opt_explain_json_namespace::context.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

◆ get_cost_tag()

virtual const char* opt_explain_json_namespace::join_ctx::get_cost_tag ( )
inlineprotectedvirtual

◆ id()

size_t opt_explain_json_namespace::join_ctx::id ( bool  hide)
virtual

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

Parameters
hideif 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.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

◆ set_sort()

virtual void opt_explain_json_namespace::join_ctx::set_sort ( sort_ctx ctx)
inlinevirtual

Set nested ORDER BY/GROUP BY/DISTINCT node to ctx.

Return values
falseOk
trueError

Reimplemented from opt_explain_json_namespace::context.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

◆ set_window()

virtual void opt_explain_json_namespace::join_ctx::set_window ( window_ctx ctx)
inlinevirtual

Set nested WINDOW node to ctx.

Return values
falseOk
trueError

Reimplemented from opt_explain_json_namespace::context.

Reimplemented in opt_explain_json_namespace::duplication_weedout_ctx, and opt_explain_json_namespace::materialize_ctx.

Member Data Documentation

◆ join_tabs

List<joinable_ctx> opt_explain_json_namespace::join_ctx::join_tabs
protected

hosted JOIN_TAB nodes

◆ sort

sort_ctx* opt_explain_json_namespace::join_ctx::sort
protected

◆ window

window_ctx* opt_explain_json_namespace::join_ctx::window
protected

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