COMMENT '', `name` VARCHAR(45) NOT NULL COMMENT '', `age` INT NOT NULL COMMENT '', `created` DATETIME NOT NULL DEFAULT NOW () COMMENT '', PRIMARY KEY (`id`) COMMENT '' ); ——શ݅Λબ͢ΔͷͰςʔϒϧεΩϟϯ SELECT * FROM demo.users; ——PRIMARY KEYʢINDEXʣΛར༻ͨ͠ྫ SELECT * FROM demo.users WHERE id > 100; ——INDEX͕ແ͍ͷͰςʔϒϧεΩϟϯ SELECT * FROM demo.users WHERE age > 20;