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Manually Pulling Data From MySQL In Rails

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Manually Pulling Data From MySQL In Rails

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Sometimes you just have to do it yourself, like when you have relationships between different databases.
Here I wanted to retrieve an array of site_ids:

    result = ActiveRecord::Base.connection.execute("SELECT * FROM sites_users WHERE user_id ='#{self.id}'")
    rows = []
    result.each_hash {|h| rows << h['site_id'].to_i }
    return rows

UPDATE: ( An easier, better way)

    rows = ActiveRecord::Base.connection.select_values("SELECT site_id FROM sites_users WHERE user_id ='#{self.id}'")
    return rows.map {|el| el.to_i }

There is also:

select_one(sql, name = nil)
select_value(sql, name = nil)
select_all(sql, name = nil) 

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