Writing array into csv file

Question

I want script save results into .csv or .txt file. My script must perform select into mssql database and send all strings from this request on email. My code:

require 'tiny_tds'
require 'csv'

@db_host  = 'myserver.com'
@db_user  = 'mylogin'
@db_pass  = 'mypassword'
client = TinyTds::Client.new(:host => @db_host, :username => @db_user, :password => @db_pass)
results = client.execute("    SELECT * FROM mydatabase    ")

results.each do |row|
p $rows = row.to_a

p h = $rows
CSV.open("data.csv", "wb") {|csv| h.to_a.each {|elem| csv << elem} }
end

My problem:

The generated csv file contains only the first line of my request. How can I write to a file all the strings of my request?

you need to put the results.each loop into the CSV.open block — Fallenhero
– Fallenhero, Commented Feb 9, 2017 at 10:08

kaspernj · Accepted Answer · 2017-02-09 11:13:00Z

1

How about this? CSV creation outside the results loop.

require 'tiny_tds'
require 'csv'

db_host  = 'myserver.com'
db_user  = 'mylogin'
db_pass  = 'mypassword'
client = TinyTds::Client.new(:host => db_host, :username => db_user, :password => db_pass)
results = client.execute("SELECT * FROM mydatabase")

CSV.open("data.csv", "wb") do |csv|
  results.each do |row|
    csv << row.to_a
  end
end

edited Feb 9, 2017 at 11:13

answered Feb 9, 2017 at 10:34

kaspernj

1,26311 silver badges16 bronze badges

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

2 Comments

Misha1991 Over a year ago

I get an error when so doing: C:/Ruby23/lib/ruby/2.3.0/csv.rb:1675:in <<': undefined method map' for nil:NilClass (NoMethodError)

kaspernj Over a year ago

I have updated the example with ".to_a" on row, which I suspect might be the reason.

Aleksei Matiushkin · Accepted Answer · 2017-02-09 10:34:43Z

0

You seem to already have a matrix inside results. So, instead of this:

results.each do |row|
  rows = row.to_a
  CSV.open("data.csv", "wb") do |csv|
    rows.to_a.each { |elem| csv << elem}
  end
end

all you need is to convert a matrix to the array of arrays and feed it to CSV:

results.map! { |row| row.to_a.map(&:to_a) }
CSV.open("data.csv", "wb") { |csv| csv.replace results }

answered Feb 9, 2017 at 10:34

Aleksei Matiushkin

121k12 gold badges109 silver badges173 bronze badges

Collectives™ on Stack Overflow

Writing array into csv file

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