For an ActiveRecord query, I can see the SQL generated without actually executing it:
SomeModel.where(something: "something").to_sql
No query was sent to the DB, but I can see the SQL as a string.
Is there anything similar that can be done for the update SQL that will be generated by some_model.save?
I think maybe not, I can't find it!
@jrochkind, If we check the API for .save here then it just calls create_or_update method. So ideally, such methods returning boolean values will not generate queries using to_sql.
Also, I think similar topic is covered here to_sql not working on update_attributes or .save
And probably there is an alternate approach such as to override ActiveRecord execute method
Even I have not seen any method to generate sql for save yet.
I also faced a situation earlier and I found that we can use the sandbox mode of rails console to verify the queries and it will be rollback the changes made in the session once we close the console.
rails console --sandbox
If you wish to test out some code without changing any data, you can do that by invoking rails console --sandbox.
@Rohan Daxini have added the reason why .to_sql is not available on save
I have this situation too.
I'm considering doing a restore of a production backup in a local environment, doing the update there and using mysqldump.
Do save within a transaction with a rollback at the end eg.
irb(main):024:0> Post.transaction do
irb(main):025:1* p=Post.create(user_id: User.first.id, text: '11', group_id: 1)
irb(main):026:1> raise ActiveRecord::Rollback
irb(main):027:1> end