[データベースシステム論] 第１２回　問い合わせ処理と最適化 SQL文

gistfile1.sql

EXPLAIN
SELECT * FROM wine_list WHERE wid = 1;

gistfile2.sql

set ENABLE_NESTLOOP to off;
EXPLAIN
SELECT * FROM wine_list WHERE wid = 1;

gistfile3.sql

set ENABLE_HASHJOIN to off;
EXPLAIN
SELECT * FROM wine_list WHERE wid = 1;

gistfile4.sql

set ENABLE_NESTLOOP to on;
set ENABLE_HASHJOIN to on;

gistfile5.sql

EXPLAIN
SELECT * 
   FROM (SELECT * FROM zipcode) AS a;

gistfile6.sql

SELECT * 
   FROM wine_list
   WHERE price > 3000;

gistfile7.sql

EXPLAIN
SELECT * 
   FROM wine_list;

gistfile8.sql

EXPLAIN
SELECT * 
   FROM wine
   WHERE price > 3000;

gistfile9.sql

EXPLAIN
SELECT * 
   FROM wine_list
   WHERE price > 3000;