Question

I have following tables

1. questions -> id, question_data, user_id
2. users -> id, fname, lname
3. question_connect-> id, question_id, user_id

My initial query was as follows

select questions.id, questions.question_data, users.id, users.fname from questions, users where questions.user_id = users.id limit 30

But over here, i want count of users on that question, so i tried following query

select questions.id, questions.question_data, users.id, users.fname, count(questions_connect.id) from questions, users LEFT JOIN questions_connect ON `questions`.`id` = `questions_connect`.`question_id` where questions.user_id = users.id group by `questions_connect`.`id` limit 30

this shows error

Unknown column 'questions.id' in 'on clause'

SO can we make 1 call with natural join and left join and if yes, where i am going wrong..?

Answer 1

Using an explicit join should sort you out:

select questions.id, questions.question_data, users.id, users.fname, count(questions_connect.id)
from questions
join users on questions.user_id = users.id
left join questions_connect on `questions`.`id` = `questions_connect`.`question_id`
group by `questions_connect`.`id`
limit 30

You’re better off specifying all your joins explicitly, try to forget that implicit joins exist.