MySQL-选择顶部后如何选择随机？

Question

I have a query like this:

SELECT Id, Name, image, price, view FROM estore.product ORDER BY view DESC LIMIT 9

and I want select random 5 records in that query. I tried but this code doesn't work:

SELECT Id, Name, Image, Price, View FROM (
    SELECT Id, Name, Image, Price, View FROM estore.product ORDER BY View DESC LIMIT 9) 
    ORDER BY RAND() LIMIT 5

How can I do? Thanks for watching?

Answer 1

A subquery must be named. Try:

LIMIT 9) as SubQueryAlias ORDER BY RAND() 
        ^^^^^^^^^^^^^^^^^^

Answer 2

You may want to go and read this thread Multiple rows alternative for RAND()

If your table is quite large (and it probably can end up quite large being a product table) the rand() limit is quite a slow query

Answer 3

SELECT Id, Name, Image, Price, View FROM estore.product ORDER BY RAND() LIMIT 5

（将子查询用于顺序并限制相同的选择是疯狂的……）