Drizzled Public API Documentation

pars0opt.h File Reference
#include "univ.i"
#include "que0types.h"
#include "usr0types.h"
#include "pars0sym.h"
#include "dict0types.h"
#include "row0sel.h"

Go to the source code of this file.

Functions

UNIV_INTERN void opt_search_plan (sel_node_t *sel_node)
UNIV_INTERN void opt_find_all_cols (ibool copy_val, dict_index_t *index, sym_node_list_t *col_list, plan_t *plan, que_node_t *exp)
UNIV_INTERN void opt_print_query_plan (sel_node_t *sel_node)

Detailed Description

Simple SQL optimizer

Created 12/21/1997 Heikki Tuuri

Definition in file pars0opt.h.


Function Documentation

UNIV_INTERN void opt_find_all_cols ( ibool  copy_val,
dict_index_t index,
sym_node_list_t *  col_list,
plan_t plan,
que_node_t *  exp 
)

Looks for occurrences of the columns of the table in the query subgraph and adds them to the list of columns if an occurrence of the same column does not already exist in the list. If the column is already in the list, puts a value indirection to point to the occurrence in the column list, except if the column occurrence we are looking at is in the column list, in which case nothing is done. in: expression or condition

Looks for occurrences of the columns of the table in the query subgraph and adds them to the list of columns if an occurrence of the same column does not already exist in the list. If the column is already in the list, puts a value indirection to point to the occurrence in the column list, except if the column occurrence we are looking at is in the column list, in which case nothing is done.

Parameters:
copy_valin: if TRUE, new found columns are added as columns to copy
indexin: index of the table to use
col_listin: base node of a list where to add new found columns
planin: plan or NULL
expin: expression or condition or NULL

Definition at line 833 of file pars0opt.cc.

References sym_node_struct::alias, func_node_struct::args, sym_node_struct::col_no, sym_node_struct::copy_val, dict_index_is_clust(), sym_node_struct::field_nos, sym_node_struct::indirection, plan_struct::must_get_clust, opt_find_all_cols(), que_node_get_next(), que_node_get_type(), SYM_CLUST_FIELD_NO, SYM_COLUMN, SYM_SEC_FIELD_NO, sym_node_struct::table, dict_index_struct::table, sym_node_struct::token_type, ut_a, UT_LIST_ADD_LAST, UT_LIST_GET_FIRST, and UT_LIST_GET_NEXT.

Referenced by opt_find_all_cols().

UNIV_INTERN void opt_print_query_plan ( sel_node_t sel_node)
UNIV_INTERN void opt_search_plan ( sel_node_t sel_node)

Optimizes a select. Decides which indexes to tables to use. The tables are accessed in the order that they were written to the FROM part in the select statement. in: parsed select node

Optimizes a select. Decides which indexes to tables to use. The tables are accessed in the order that they were written to the FROM part in the select statement.

Parameters:
sel_nodein: parsed select node

Definition at line 1103 of file pars0opt.cc.

References sel_node_struct::asc, order_node_struct::asc, sym_tab_struct::heap, mem_heap_alloc(), sel_node_struct::n_tables, opt_print_query_plan(), opt_search_plan(), sel_node_struct::order_by, sel_node_struct::plans, que_node_get_next(), sym_node_struct::table, and sel_node_struct::table_list.

Referenced by opt_search_plan(), and pars_select_statement().