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Rails: How to remove (and resuse) all existing constraints from ActiveRecord::Relation

+2 votes
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I'd like to remove all existing constraints from an ActiveRecord::Relation and leave the rest in-tact.
I am NOT looking for #unscoped since I would like to keep any joins/order clauses around.

Additionally, I would like to re-use the constraints that were removed in another query, so the ability to call #to_sql on them would be a very nice bonus.

This is the best I've been able to hack together:

Order.where(id: 1).where(id: 2).arel.constraints[0].to_sql
 => "`orders`.`id` = 1 AND `orders`.`id` = 2"

...but that just seems wrong. As far as I can tell #constraints always has one item in it, but I don't know that will always be true.

posted Dec 29, 2014 by anonymous

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