如何在子查询中使用一个SQL查询的结果

Question

I have to answer the following question

"For each year in the database, list the year and the total number of movies that were released in that year, showing these totals in decreasing order. That is, the year(s) with the largest number of movies appear first. If some years have the same number of movies, show these in increasing order of year."

Currently I am using the code below to get the movies to group together, but am unable to get them to sort:

Select YearReleased, count(*)                
from Movies                             
group by YearReleased 

I wish to use something to order this and am trying to make a sub query that uses the results of the first query, along the lines of:

(select * from results order by count(*))

but so far I have been unsuccessful. How do I achieve this or is there a better way of getting the results in that order?

Answer 1

"Unsuccessful" isn't very useful, as opposed to actual error text -- and you aren't telling us which vendor's database you're running against, so we can't test. That said, the following should work:

select
  YearReleased,
  count(*) as movie_count
  from movies
  group by YearReleased
  order by movie_count desc, YearReleased;

No subqueries needed!

Validated against SQLite 3.5.9; if running against something less standards-compliant (which SQLite is , except in very explicitly documented ways), your mileage may vary.

Answer 2

从*中选择*（从YearReleased从Movies组中选择YearReleased，count（*）作为NumReleased）由NumReleased排序

Answer 3

select * from (select YearReleased, count(*) counter
from Movies
group by YearReleased 
) a order by counter

May need a syntax change depending on your sql flavour.

Answer 4

在第一个查询中：选择yearReleased，在第二个查询中将count（*） 作为'count1' ：按count1排序

Answer 5

是的，使用聚合，您可以为count（*）放置一个别名，并且可以将其作为一列引用。