Select Max Data from Subquery SQL, but it Show All Results from Subquery

问题

SELECT MAX( t.valuesum ) AS total, t.codebook
FROM (
    SELECT SUM( value ) AS valuesum, codebook
    FROM stock
    GROUP BY codebook
) t
GROUP BY t.codebook

In the subquery, the output is :

b001 35,
b002 20,
b0003 11

I want to only see: b001 35. Please help me.

回答1:

1st solution using where condition:

SELECT t1.valuesum, t1.codebook
FROM (
        SELECT SUM( s.value ) AS valuesum, s.codebook
        FROM stock s
        GROUP BY s.codebook
     ) t1
WHERE t1.valuesum in (SELECT MAX( t2.valuesum ) AS total
                     FROM (
                             SELECT SUM( s2.value ) AS valuesum, s2.codebook
                             FROM stock s2
                             GROUP BY s2.codebook
                           )t2
                     )

SQL Fiddle Demo

2nd solution using having condition:

SELECT max(t1.valuesum), t1.codebook
FROM (
        SELECT SUM( s.value ) AS valuesum, s.codebook
        FROM stock s
        GROUP BY s.codebook
     ) t1
GROUP BY t1.codebook
HAVING max(t1.valuesum) = (SELECT MAX( t2.valuesum ) AS total
                     FROM (
                             SELECT SUM( s2.value ) AS valuesum, s2.codebook
                             FROM stock s2
                             GROUP BY s2.codebook
                           )t2
                     )

SQL Fiddle Demo

回答2:

Try this

SELECT SUM( value ) AS valuesum, codebook 
FROM stock 
GROUP BY codebook
ORDER BY valuesum DESC
LIMIT 1

回答3:

You can simple get it by single query -

    SELECT MAX( t2.valuesum ) AS valuesum, t2.codebook
    FROM (
          SELECT SUM( s2.value ) AS valuesum, s2.codebook
          FROM stock s2
          GROUP BY s2.codebook
         )t2

DEMO : - http://sqlfiddle.com/#!9/c2534/15

回答4:

Try this

SELECT TOP 1 * FROM
(
  SELECT SUM([value]) AS valuesum, codebook
  FROM stock
  GROUP BY codebook
)
ORDER BY valuesum DESC

回答5:

Assuming (from the comments and the error messages) that you use MySQL:

SELECT SUM( value ) AS valuesum, codebook
FROM stock
GROUP BY codebook
ORDER BY valuesum DESC
  LIMIT 1 ;

来源：https://stackoverflow.com/questions/12562389/select-max-data-from-subquery-sql-but-it-show-all-results-from-subquery

标签

mysql

sql

subquery