CREATE INDEX

CREATE INDEX

The table games shows the year and the city hosting the Olympic Games.

games

yr	city
2000	Sydney
2004	Athens
2008	Beijing
2012	London

schema:scott

 DROP TABLE games

 CREATE TABLE games(
  yr INTEGER PRIMARY KEY,
  city VARCHAR(20));
INSERT INTO games VALUES (2000,'Sydney');
INSERT INTO games VALUES (2004,'Athens');
INSERT INTO games VALUES (2008,'Beijing');
INSERT INTO games VALUES (2012,'London');

When you create an index you make it faster to find a particular row. You can also make the JOIN operator faster.

CREATE INDEX gamesIdx ON games(city,yr);
SELECT yr, city FROM scott.games

CREATE INDEX gamesIdx ON games(city,yr);
SELECT yr, city FROM games

See also

• SELECT Tutorial
• SELECT WHERE