Mysql database - connection query

The first 1 Turn off ： Internal connection query

USE School;

##########  Query the students' names and corresponding classes in the data table  ##########
# Please add the implementation code here 
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select tb_student.name as studentName,tb_class.name as className from tb_student inner join tb_class on tb_student.class_id = tb_class.id;

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The first 2 Turn off ： External connection query

USE School;

##########  Use the left outer connection to query the names of all students and the corresponding classes  ##########

# Please add the implementation code here 
########## Begin ##########
select tb_student.name as studentName,tb_class.name as className from tb_student left join tb_class on tb_student.class_id = tb_class.id;

select tb_student.name as studentName,tb_class.name as className from tb_student right join tb_class on tb_student.class_id = tb_class.id;

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##########  Use the right external connection to query all student names and corresponding classes  ##########

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




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The first 3 Turn off ： Composite conditional join query

USE School;

##########  Check the scores of all classes in 90 The name of the student with a score of above, the student's grade and the class in which the student belongs  ##########
# Please add the implementation code here 
########## Begin ##########
select tb_student.name as studentName,tb_student.score, tb_class.name as className from tb_student join tb_class on tb_student.class_id =tb_class.id  where score > 90 ;



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