SELECT * FROM dj LEFT OUTER JOIN lx ON dj.编号=lx.编号;
SELECT * FROM dj RIGHT OUTER JOIN lx ON dj.编号=lx.编号;
SELECT * FROM game
SELECT * FROM 王者荣耀 AS aa game
SELECT 类型 FROM game
SELECT DISTINCT 类型 FROM game
SELECT DISTINCT aa.类型 AS bb FROM 王者荣耀.game AS aa
SELECT * FROM game WHERE 类型='法师'
SELECT * FROM game WHERE 类型 LIKE '法师'
SELECT * FROM game WHERE 类型='法师'AND 等级 <30
SELECT * FROM game WHERE 等级 >=60 AND 等级 <=80
SELECT 等级,姓名 FROM game
SELECT * FROM game WHERE 姓名 LIKE '李%'
SELECT * FROM game WHERE 姓名 LIKE '_小%'
SELECT * FROM game WHERE 姓名 LIKE '%信%'
SELECT * FROM game WHERE 姓名 LIKE'_信%'
SELECT * FROM game WHERE 姓名 LIKE '_信';
SELECT 等级 * 10 AS aa FROM game
SELECT 编号 * 等级 AS aa FROM game
SELECT * FROM game WHERE 类型!='法师'
SELECT * FROM game WHERE NOT 类型='法师'
SELECT * FROM game WHERE NOT 等级 <=60;
SELECT * FROM game WHERE 类型 IS NULL;
SELECT * FROM game WHERE NOT 类型 IS NULL;
SELECT * FROM game WHERE 姓名 IN ('李白','李广','武则天')
SELECT * FROM game WHERE 姓名='李白' OR 姓名='李广' OR 姓名='武则天'
SELECT * FROM game WHERE LIKE
