How to check if record exists in ruby - ruby

I'm using Ruby 1.9.3, MS Sql Server and Windows 7 Ultimate
I'd like to know how to check if a certain record is already existing in the database so that I would avoid duplicate records. In rails it would have been easy to just invoke Object.exists? but I'm using Ruby only.
Thanks


Check the source code for exists? in activerecord
It basically checks if there primary key with the id exists already using sql query.
you can use these to write your own helper method.
or else u can also use activerecord gem in ruby too.

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