PHP | left join avg query give me Array()

I’m trying to implement a query within my code that gives me the ability to calculate the average value between the ratings received and the number of ratings per post, and sort posts from the one with the highest rating to to the one with the lowest average rating

db value

looking at the following table and implementing this query everything works perfectly.

the problem happens when I want to get a left join with the comments table:

db value

even if the query is correct:

doing the print_r($ results); i get: Array( )

and I don’t understand why, understanding this step is essential for me to make the next join with the post table, so that I can get all the values ​​out, why do I get array ()?

how can i fix it?

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