Question

I have a bit multidimensional array like this one:

[[2, 1], [751, 159], [793, 195], [978, 527], [938, 783], [977, 881], [713, 592, 101], [337, 248, 143], [444, 647, 196], [913, 763, 211], [752, 746, 225], [862, 878, 373], [876, 900, 597], [719, 904, 236, 11], [448, 836, 883, 59], [486, 723, 241, 150], [864, 611, 619, 167], [558, 796, 707, 353], [915, 683, 738, 534], [641, 777, 892, 107, 78], [264, 310, 161, 574, 114], [549, 849, 596, 181, 160], [633, 471, 497, 438, 262], [351, 485, 544, 772, 348], [890, 941, 572, 418, 374], [776, 972, 1001, 729, 379], [595, 898, 989, 771, 454], [84, 514, 914, 571, 442, 19], [335, 97, 689, 314, 879, 20], [869, 828, 802, 859, 553, 34], [298, 134, 564, 614, 411, 62], [175, 579, 490, 399, 479, 72], [382, 830, 215, 691, 624, 85], [922, 840, 657, 917, 436, 95]] 

As you can see, each sub array has between 2 and 6 values.

I have a model called “Sub” with db columns “sub1”, “sub2”, “sub3”, “sub4”, “sub5”, “sub6”. (values for sub3-6 would be null if the sub array only had 2 values)

What is the proper way to save each sub array to a db row?

I have tried this:
@m = [the big array I mentioned above]

      @m.each do |t|
        Pair.create(:sub1 => t[0], :sub2 => t[1], :sub3 => t[2], :sub4 => t[3], :sub5 => t[4], :sub6 => t[5])
      end

But for some reason that creates a table that does this: (sample of “sub1” column)

2
2
751
2
751
793
2
751
793
978
2
751
793
978
938

See what’s happening there? It repeats each but adds one more row each time.

Here’s my model:

class Pair < ActiveRecord::Base
  attr_accessible :id, :sub1, :sub2, :sub3, :sub4, :sub5, :sub6
end

UPDATE: I figured out the issue… I had the create method in the wrong part of a script and that was causing it to run several times in a row in a weird way. Thanks everyone!

Answer 1

One way would be to serialize the column. See here: http://api.rubyonrails.org/classes/ActiveRecord/Base.html#method-c-serialize at the Saving arrays, hashes, and other non-mappable objects in text columns section.