query graph

/* Query graph query thread node: the fields are protected by the kernel
mutex with the exceptions named below */
struct que_thr_struct{
 que_common_t common;  /*!< type: QUE_NODE_THR */
 ulint  magic_n; /*!< magic number to catch memory
     corruption */
 que_node_t* child;  /*!< graph child node */
 que_t*  graph;  /*!< graph where this node belongs */
 ibool  is_active; /*!< TRUE if the thread has been set
     to the run state in
     que_thr_move_to_run_state, but not
     deactivated in
     que_thr_dec_reference_count */
 ulint  state;  /*!< state of the query thread */
 UT_LIST_NODE_T(que_thr_t)
   thrs;  /*!< list of thread nodes of the fork
     node */
 UT_LIST_NODE_T(que_thr_t)
   trx_thrs; /*!< lists of threads in wait list of
     the trx */
 UT_LIST_NODE_T(que_thr_t)
   queue;  /*!< list of runnable thread nodes in
     the server task queue */
 /*------------------------------*/
 /* The following fields are private to the OS thread executing the
 query thread, and are not protected by the kernel mutex: */
 que_node_t* run_node; /*!< pointer to the node where the
     subgraph down from this node is
     currently executed */
 que_node_t* prev_node; /*!< pointer to the node from which
     the control came */
 ulint  resource; /*!< resource usage of the query thread
     thus far */
 ulint  lock_state; /*!< lock state of thread (table or
     row) */
 ulint  fk_cascade_depth; /*!< maximum cascading call depth
     supported for foreign key constraint
     related delete/updates */
};
 
#define QUE_THR_MAGIC_N  8476583
#define QUE_THR_MAGIC_FREED 123461526
 
/* Query graph fork node: its fields are protected by the kernel mutex */
struct que_fork_struct{
 que_common_t common;  /*!< type: QUE_NODE_FORK */
 que_t*  graph;  /*!< query graph of this node */
 ulint  fork_type; /*!< fork type */
 ulint  n_active_thrs; /*!< if this is the root of a graph, the
     number query threads that have been
     started in que_thr_move_to_run_state
     but for which que_thr_dec_refer_count
     has not yet been called */
 trx_t*  trx;  /*!< transaction: this is set only in
     the root node */
 ulint  state;  /*!< state of the fork node */
 que_thr_t* caller;  /*!< pointer to a possible calling query
     thread */
 UT_LIST_BASE_NODE_T(que_thr_t)
   thrs;  /*!< list of query threads */
 /*------------------------------*/
 /* The fields in this section are defined only in the root node */
 sym_tab_t* sym_tab; /*!< symbol table of the query,
     generated by the parser, or NULL
     if the graph was created 'by hand' */
 pars_info_t* info;  /*!< info struct, or NULL */
 /* The following cur_... fields are relevant only in a select graph */
 ulint  cur_end; /*!< QUE_CUR_NOT_DEFINED, QUE_CUR_START,
     QUE_CUR_END */
 ulint  cur_pos; /*!< if there are n rows in the result
     set, values 0 and n + 1 mean before
     first row, or after last row, depending
     on cur_end; values 1...n mean a row
     index */
 ibool  cur_on_row; /*!< TRUE if cursor is on a row, i.e.,
     it is not before the first row or
     after the last row */
 sel_node_t* last_sel_node; /*!< last executed select node, or NULL
     if none */
 UT_LIST_NODE_T(que_fork_t)
   graphs;  /*!< list of query graphs of a session
     or a stored procedure */
 /*------------------------------*/
 mem_heap_t* heap;  /*!< memory heap where the fork was
     created */
};
 

/* Query graph node types */
#define QUE_NODE_LOCK  1
#define QUE_NODE_INSERT  2
#define QUE_NODE_UPDATE  4
#define QUE_NODE_CURSOR  5
#define QUE_NODE_SELECT  6
#define QUE_NODE_AGGREGATE 7
#define QUE_NODE_FORK  8
#define QUE_NODE_THR  9
#define QUE_NODE_UNDO  10
#define QUE_NODE_COMMIT  11
#define QUE_NODE_ROLLBACK 12
#define QUE_NODE_PURGE  13
#define QUE_NODE_CREATE_TABLE 14
#define QUE_NODE_CREATE_INDEX 15
#define QUE_NODE_SYMBOL  16
#define QUE_NODE_RES_WORD 17
#define QUE_NODE_FUNC  18
#define QUE_NODE_ORDER  19
#define QUE_NODE_PROC  (20 + QUE_NODE_CONTROL_STAT)
#define QUE_NODE_IF  (21 + QUE_NODE_CONTROL_STAT)
#define QUE_NODE_WHILE  (22 + QUE_NODE_CONTROL_STAT)
#define QUE_NODE_ASSIGNMENT 23
#define QUE_NODE_FETCH  24
#define QUE_NODE_OPEN  25
#define QUE_NODE_COL_ASSIGNMENT 26
#define QUE_NODE_FOR  (27 + QUE_NODE_CONTROL_STAT)
#define QUE_NODE_RETURN  28
#define QUE_NODE_ROW_PRINTF 29
#define QUE_NODE_ELSIF  30
#define QUE_NODE_CALL  31
#define QUE_NODE_EXIT  32
 

/* Insert node structure */
struct ins_node_struct{
 que_common_t common; /*!< node type: QUE_NODE_INSERT */
 ulint  ins_type;/* INS_VALUES, INS_SEARCHED, or INS_DIRECT */
 dtuple_t* row; /*!< row to insert */
 dict_table_t* table; /*!< table where to insert */
 sel_node_t* select; /*!< select in searched insert */
 que_node_t* values_list;/* list of expressions to evaluate and insert in an INS_VALUES insert */
 ulint  state; /*!< node execution state */
 dict_index_t* index; /*!< NULL, or the next index where the index entry should be inserted */
 dtuple_t* entry; /*!< NULL, or entry to insert in the index; after a successful insert of the entry, this should be reset to NULL */
 UT_LIST_BASE_NODE_T(dtuple_t)    entry_list;/* list of entries, one for each index */
 byte*  row_id_buf;/* buffer for the row id sys field in row */
 trx_id_t trx_id; /*!< trx id or the last trx which executed the node */
 byte*  trx_id_buf;/* buffer for the trx id sys field in row */
 mem_heap_t* entry_sys_heap;
    /* memory heap used as auxiliary storage;
    entry_list and sys fields are stored here;
    if this is NULL, entry list should be created
    and buffers for sys fields in row allocated */
 ulint  magic_n;
};
 
 
 

/** Select statement node */
struct sel_node_struct{
 que_common_t common;  /*!< node type: QUE_NODE_SELECT */
 enum sel_node_state
   state; /*!< node state */
 que_node_t* select_list; /*!< select list */
 sym_node_t* into_list; /*!< variables list or NULL */
 sym_node_t* table_list; /*!< table list */
 ibool  asc;  /*!< TRUE if the rows should be fetched
     in an ascending order */
 ibool  set_x_locks; /*!< TRUE if the cursor is for update or
     delete, which means that a row x-lock
     should be placed on the cursor row */
 ulint  row_lock_mode; /*!< LOCK_X or LOCK_S */
 ulint  n_tables; /*!< number of tables */
 ulint  fetch_table; /*!< number of the next table to access
     in the join */
 plan_t*  plans;  /*!< array of n_tables many plan nodes
     containing the search plan and the
     search data structures */
 que_node_t* search_cond; /*!< search condition */
 read_view_t* read_view; /*!< if the query is a non-locking
     consistent read, its read view is
     placed here, otherwise NULL */
 ibool  consistent_read;/*!< TRUE if the select is a consistent,
     non-locking read */
 order_node_t* order_by; /*!< order by column definition, or
     NULL */
 ibool  is_aggregate; /*!< TRUE if the select list consists of
     aggregate functions */
 ibool  aggregate_already_fetched;
     /*!< TRUE if the aggregate row has
     already been fetched for the current
     cursor */
 ibool  can_get_updated;/*!< this is TRUE if the select
     is in a single-table explicit
     cursor which can get updated
     within the stored procedure,
     or in a searched update or
     delete; NOTE that to determine
     of an explicit cursor if it
     can get updated, the parser
     checks from a stored procedure
     if it contains positioned
     update or delete statements */
 sym_node_t* explicit_cursor;/*!< not NULL if an explicit cursor */
 UT_LIST_BASE_NODE_T(sym_node_t)
   copy_variables; /*!< variables whose values we have to
     copy when an explicit cursor is opened,
     so that they do not change between
     fetches */
};
 
 

/** Commit command node in a query graph */
struct commit_node_struct{
	que_common_t	common;	/*!< node type: QUE_NODE_COMMIT */
	enum commit_node_state
			state;	/*!< node execution state */
};

/* Index create node struct */
struct ind_node_struct{
 que_common_t common; /*!< node type: QUE_NODE_INDEX_CREATE */
 dict_index_t* index; /*!< index to create, built as a memory data
    structure with dict_mem_... functions */
 ins_node_t* ind_def; /* child node which does the insert of
    the index definition; the row to be inserted
    is built by the parent node  */
 ins_node_t* field_def; /* child node which does the inserts of
    the field definitions; the row to be inserted
    is built by the parent node  */
 commit_node_t* commit_node;
    /* child node which performs a commit after
    a successful index creation */
 /*----------------------*/
 /* Local storage for this graph node */
 ulint  state; /*!< node execution state */
 ulint  page_no;/* root page number of the index */
 dict_table_t* table; /*!< table which owns the index */
 dtuple_t* ind_row;/* index definition row built */
 ulint  field_no;/* next field definition to insert */
 mem_heap_t* heap; /*!< memory heap used as auxiliary storage */
};

 Query graph fork node 可有多个 Query graph query thread node， 并行查询

(Query graph query thread node)->child = 具体要执行操作的node