MYSQL Error... Can anyone help?

rubyonrails-talk
1

Hi there, I am working through a tutorial and I'm at the point of accepting or declining a friend request.

However, whenever I click accept of decline, I get the following error:

Mysql::Error: Column 'created_at' in order clause is ambiguous: SELECT `users`.id FROM `users` INNER JOIN `friendships` ON `users`.id = `friendships`.friend_id WHERE (`users`.`id` = 115) AND ((`friendships`.user_id = 114) AND ((status = 'requested'))) ORDER BY created_at LIMIT 1

I've looked through the controller for these 2 actions, but nothing stands out.

Please can anyone suggest how to fix this?

Many Thanks

2

Either in your User has_many :friendships declaration or the User.find that joins :friendships in the controller you have :order => "created_at". The RDBMS can't know which table to use for created_at column, as both have one. You need to specify that.

3

makes sense i think, but how would i specify it?

4

Actually, for now - commenting the :order out in User.rb seems to allow me to continue without issue. :slight_smile:

thanks for the advice - it made me look in the right direction.

5

makes sense i think, but how would i specify it?

> > > > > > > Hi there, I am working through a tutorial and I'm at the point of > > accepting or declining a friend request. > > > However, whenever I click accept of decline, I get the following > > error: > > > Mysql::Error: Column 'created_at' in order clause is ambiguous: SELECT > > `users`.id FROM `users` INNER JOIN `friendships` ON `users`.id = > > `friendships`.friend_id WHERE (`users`.`id` = 115) AND > > ((`friendships`.user_id = 114) AND ((status = 'requested'))) ORDER BY > > created_at LIMIT 1 > > > I've looked through the controller for these 2 actions, but nothing > > stands out. > > > Please can anyone suggest how to fix this? > > > Many Thanks > > Either in your User has_many :friendships declaration or the User.find > that joins :friendships in the controller you have :order => > "created_at". The RDBMS can't know which table to use for created_at > column, as both have one. You need to specify that.

6

This is an error in the SQL statement being generated. The created_at column exists in both the Users and Friendships tables. You need to indicate the table of the column you want to order by.

Example: ".... ORDER BY users.created_at LIMIT 1"