Mysql database - single table query (III)

The first 1 Turn off ： Sort query results

USE School;

# Please add the implementation code here 
########## Begin ##########

##########  Inquire about 1 All the information of the class will be displayed in descending order  ##########
select * from tb_score where class_id=1 order by score desc;

########## End ##########

The first 2 Turn off ： Group query

USE School;

# Please add the implementation code here 
########## Begin ##########

##########  Group query the class name  ##########

select * from tb_class group by class_id;

########## End ##########

  The first 3 Turn off ： Use LIMIT Limit the number of query results

USE School;

# Please add the implementation code here 
########## Begin ##########

##########  Query the... In the class 2 Name to number 5 Student information of name  ##########
select * from tb_score order by score desc limit 1,4;

########## End ##########