Comments (3)
Someone else just casted and showed this solution:
SELECT posts.mentor_name, COUNT(likes.post_num)
FROM likes INNER JOIN posts
ON likes.post_num = posts.num
GROUP BY posts.mentor_name
Which shows you don't need to link on name, but you do still link on "num" rather than "id" which I still find a wee bit confusing.
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@ZooeyMiller , you're right about it being good practice to put an id in the table as a primary key, but you can still join by any column you'd like and it doesn't have to be the id.
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Closing, this is now outdated
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Related Issues (20)
- add author & maintainer to readme HOT 1
- Suggest Heroku rather than ElephantSQL HOT 1
- Add tables to show expected results. HOT 1
- typo in readme location instead of london
- Typo
- Error message for db_url
- Url given in quotations by Heroku
- Rewording challenge one.
- Change 'num' in posts to id
- Expected result for books reserved for a time greater than the average reservation time is wrong
- why host on heroku rather than locally? HOT 4
- Wrong column names in Readme HOT 2
- Small change to set up instructions
- PG security vulnarability HOT 1
- Add instructions for adding a heroku db on the website
- Solution is in branch and is broken HOT 1
- Hangs after running db build
- Do we need the database directory? HOT 2
- SSH vs HTTPS link HOT 2
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