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How can I highlight two columns to count by group?

When I do this

SELECT id, gender, count(1)
FROM class_student
WHERE id = 1
GROUP BY gender

I get

id  gender    count
--------------------
1   female    10
1   male      5

How can I get this?

id female male
---------------
1  10     5

Is the following query the correct way to do this?

SELECT
    id,
    (select count(1) from class_student
     where id = 1 AND gender='female') AS female,
    (select count(1) from class_student
     where id = 1 AND gender='male') AS male
FROM class_student
GROUP BY id
+3


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2 answers


you can use select with case when



  SELECT id
         , sum(case when gender = 'male' then 1 else 0 end) male, 
         , sum(case when gender = 'female' then 1 else 0 end) female
    FROM class_student
    WHERE id = 1
    GROUP BY id
+1


source


You can use CASES :



SELECT id, SUM(case when gender = 'male' then 1 else 0 end) male, SUM(case when gender = 'female' then 1 else 0 end) female
    FROM CLASS_STUDENT
    WHERE id = 1
    GROUP BY id;
+1


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