row0sel.ic File Reference

Select. More...

#include "que0que.h"

Functions
static plan_t *	sel_node_get_nth_plan (sel_node_t *node, ulint i)
	Gets the plan node for the nth table in a join. More...
static void	sel_node_reset_cursor (sel_node_t *node)
	Resets the cursor defined by sel_node to the SEL_NODE_OPEN state, which means that it will start fetching from the start of the result set again, regardless of where it was before, and it will set intention locks on the tables. More...
static que_thr_t *	open_step (que_thr_t *thr)
	Performs an execution step of an open or close cursor statement node. More...
static dberr_t	row_search_for_mysql (byte *buf, page_cur_mode_t mode, row_prebuilt_t *prebuilt, ulint match_mode, ulint direction)
	Searches for rows in the database. More...

Detailed Description

Select.

Created 12/19/1997 Heikki Tuuri

Function Documentation

open_step()

static que_thr_t * open_step ( que_thr_t *  thr )

inlinestatic

Performs an execution step of an open or close cursor statement node.

Returns

query thread to run next or NULL

Parameters

thr	in: query thread

row_search_for_mysql()

static dberr_t row_search_for_mysql ( byte *  buf, page_cur_mode_t  mode, row_prebuilt_t *  prebuilt, ulint  match_mode, ulint  direction  )

inlinestatic

Searches for rows in the database.

This is used in the interface to MySQL. This function opens a cursor, and also implements fetch next and fetch prev. NOTE that if we do a search with a full key value from a unique index (ROW_SEL_EXACT), then we will not store the cursor position and fetch next or fetch prev must not be tried to the cursor!

Parameters

[out]	buf	buffer for the fetched row in MySQL format
[in]	mode	search mode PAGE_CUR_L
[in,out]	prebuilt	prebuilt struct for the table handler; this contains the info to search_tuple, index; if search tuple contains 0 field then we position the cursor at start or the end of index, depending on 'mode'
[in]	match_mode	0 or ROW_SEL_EXACT or ROW_SEL_EXACT_PREFIX
[in]	direction	0 or ROW_SEL_NEXT or ROW_SEL_PREV; Note: if this is != 0, then prebuilt must has a pcur with stored position! In opening of a cursor 'direction' should be 0.

Returns

DB_SUCCESS, DB_RECORD_NOT_FOUND, DB_END_OF_INDEX, DB_DEADLOCK, DB_LOCK_TABLE_FULL, DB_CORRUPTION, or DB_TOO_BIG_RECORD

sel_node_get_nth_plan()

static plan_t * sel_node_get_nth_plan ( sel_node_t *  node, ulint  i  )

inlinestatic

Gets the plan node for the nth table in a join.

Returns

plan node

Parameters

node	in: select node
i	in: get ith plan node

sel_node_reset_cursor()

static void sel_node_reset_cursor ( sel_node_t *  node )

inlinestatic

Resets the cursor defined by sel_node to the SEL_NODE_OPEN state, which means that it will start fetching from the start of the result set again, regardless of where it was before, and it will set intention locks on the tables.

Parameters

node	in: select node