SQL语句19问

  

   SELECT*FROM user
  

SELECT*FROM user WHERE score>80；

SELECT*FROM user WHERE gender='男';

SELECT students FROM user WHERE students LIKE'小%';

SELECT*FROM user WHERE students LIKE'%聪%'；

SELECT*FROM user WHERE score IN(98,60,92);

  

   SELECT*FROM user WHERE score>95 OR gender='女';
  

  

   SELECT*FROM user,user_ext WHERE user.id=user_ext.id;
  

  

   SELECT COUNT(*)FROM user WHERE score>60;
  

  

   SELECT AVG(score) FROM user;
  

  

   SELECT SUM(score)AS SUMVALUE FROM user;
  

  

   SELECT MAX(score)AS MAXVALUE FROM user;
  

  

   SELECT MIN(score)AS MINVALUE FROM user;
  

  

   SELECT DISTINCT(age)AS 年龄 FROM user_ext;
  

  

   SELECT*FROM user_ext ORDER BY weight DESC;
  

  

   SELECT t1.id,t1.students,t2.age,t2.weight FROM user AS t1 LEFT JOIN user_ext AS t2 ON t2. id=t1.id WHERE t2.age>9;
  

  

   CREATE TABLE test(id Integer Primary Key,students VarChar(8),score Integer,gender VarChar(2));
  

  

   DROP TABLE test;
  

  

   DELETE FROM user WHERE students='小明';
  

  

   INSERT INTO user(students,score,gender)VALUES('小蜗牛',100,'男');