Go through http://blog.csdn.net/anxpp/article/details/51893792 interview questions in the inside, I see, when the inside of the select statement is
Select * from grade g
The where (
Select count (*) from grade where right ourse=course and g.g rade) & lt; 3
The order by course, grade desc

Can you help to check it, this inside the logical relations in the where clause? Thank humbly the

CodePudding user response:

The SQL is problematic, take each course result in the first three, had better have analysis function,

CodePudding user response:

To benchmark the current behavior, find a large number of records than himself, there was a man older than you, you are the second place, two people older than you, you are the third place,

CodePudding user response:

refer to the second floor wmxcn2000 response:

to benchmark the current behavior, find a large number of records than they are, there is a person older than you, you are second, two people older than you, you are the third,

SQL does not take into account two or more than two tied for first, also did not consider two or more than two tied for second,
So SQL is problematic,