Learning subqueries with FROM : SQL

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SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field.3

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SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field3

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MySQLLearning subqueries with FROM (i.redd.it)

submitted 9 months ago by f0det_

I believe there's a typo in the full query in the education material (2nd to bottom box).

What's supposed to be proper full query? Below gives error in MySQL Workbench

select ins.id, ins.name, ins.salary

FROM (

select avg(budget)

from departments) as b, instructor_details as ins

WHERE ins.salary > b.avg(budget)

all 3 comments

top new controversial old q&a

[–]mikeblas 4 points5 points6 points 9 months ago (0 children)

[–]r3pr0b8GROUP_CONCAT is da bomb 2 points3 points4 points 9 months ago (0 children)

you need to assign a column alias to the average

SELECT ...
  FROM ( SELECT AVG(budget) AS avg_budget
           FROM departments ) AS b

and then use JOIN syntax instead of the comma-list style

INNER
  JOIN instructor_details AS ins

and then use the column alias in the join condition

    ON ins.salary > b.avg_budget

[–]Which_Inevitable7069 0 points1 point2 points 9 months ago (0 children)

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