Ruby CSV | How to skip few columns while reading CSV?

Question

I am bulk importing data from a CSV file into database using Active record Import gem. But I want to skip few CSV columns when importing.

For example, my xaa.csv has headers like name, author, author_id, rating. While importing, I want to skip the 'author_id' column values and import all the other columns.

books = CSV.read("/public/xaa.csv") //What more should I do here to skip the 3rd column
columns = [:name, :author, :rating]
Book.import columns, books, :validate => false

What have you tried? Have you looked at the headers option. Read the headers and then you can selectively import each row based on the column. I do that all the time — MageeWorld
– MageeWorld, Commented Dec 22, 2016 at 17:02

vegetaras · Accepted Answer · 2016-12-22 17:32:07Z

7

books = []

CSV.foreach('/public/xaa.csv', headers: true) do |row|
  books << [row['name'], row['author'], row['rating']]
end

columns = [:name, :author, :rating]
Book.import(columns, books, validate: false)

answered Dec 22, 2016 at 17:32

vegetaras

1194 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

whodini9 Over a year ago

This is functionally no different than the original code. For the "how to skip 3rd column" requirement, you need to set row['rating'] = nil, or replace nil in the 3rd position in the books << line

TheGuy Over a year ago

Thankyou @vegetaras.

andynu · Accepted Answer · 2016-12-22 19:21:27Z

2

books = CSV.readlines(path, headers:true).map{|row| row.values_at('name','rating') }

vegetaras's version is slightly more memory efficient.

answered Dec 22, 2016 at 19:21

andynu

7325 silver badges15 bronze badges

Collectives™ on Stack Overflow

Ruby CSV | How to skip few columns while reading CSV?

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related