Rails which method to create row in DB when having an array?

Question

Here is the array data:

data =  [

        # == DB Seeds == 
            ["name", "Peter", "Pan", "Ulla"],
            ["t_u_a", "4405", "6710", "8010"],
            ["t_u_b", "5590", "5590", "9080"]

]

It is column name, value, value, value.

Does Rails have a nice create method for arrays?

Instead of my having to write:

    Product.create([{ name: 'Peter', tu_a_a: '4405', tu_a_b: '5590' },

    { name: 'Pan', tu_a_a: '6710', tu_a_b: '5590'  }, 

    { name: 'Ulla', tu_a_a: '8010', tu_a_b: '9080'  }])

Update:

[{"name"=>"name", "Peter"=>"Peter", "Pan"=>"Pan", "Ulla"=>"Ulla", nil=>nil}, 

{"name"=>"t_u_a", "Peter"=>"4405", "Pan"=>"6710", "Ulla"=>"8010", nil=>nil}, 

{"name"=>"t_u_b", "Peter"=>"5590", "Pan"=>"5590", "Ulla"=>"9080", nil=>nil}]

Rails beginner · Accepted Answer · 2013-02-19 18:09:17Z

3

You can use the ActiveRecord create function, but first you're need to reformat your data as an array of hashes, instead a 2d array where the first array is the column names. Here is a quick function to do that (if you use this, make sure you test it, because I haven't) -

def convert_to_hashes(my_array)
    keys = my_array.map {|d| d[0]}
    new_array = []
    count = 0

    (1..my_array[0][0].length-1).each do |values|
        new_hash = {}
        count += 1
       (0..keys.length-1).each do |index|
            new_hash[keys[index]] = my_array[index][count]
        end
        new_array << new_hash
    end

    new_array
end

So then you end up with [your model name].create(convert_to_hashes(my_data))

edited Feb 19, 2013 at 18:09

Rails beginner

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answered Feb 19, 2013 at 16:29

Scott S

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5 Comments

Rails beginner Over a year ago

I have just tried your solution, have updated my question with the output. The keys are wrong.

Rails beginner Over a year ago

Change the keys to my_array.map {|d| d[0]}

Scott S Over a year ago

I have updated this function to fix the issue you were seeing with the column names being treated as the first value set. This should also take care of the nil key/value at the end. Other than that, however, the values look correct. Also, map is a nicer way of doing it - once you've tweaked out all the bugs, feel free to post the final function for others. But, you get the idea - convert the data and use the create function.

Michael Papile Over a year ago

You may also benefit from using inject for the my_array.each loop. Good answer though.

Rails beginner Over a year ago

I have a some problems with the values: pastie.org/private/1xqsieperan2zjxqstubta#19

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