CODEWITHSUNDEEP
ruby-on-railsloops
oprogfrogo
oprogfrogo

Reputation: 2074

How to Iterate through Column Names from execute sql results

I'm trying to iterate through each column name from my results to place in the first row of my view. I'm using the execute sql way to querying the database.

I've got this so far but it's not outputting what I need:

<% for columns in @results %>
  <tr>
    <% @results.each do |column, value| %>
      <td><%= column %></td>
    <% end %>
  </tr>
<% end %>

Upvotes: 0

Views: 4371

Answers (2)

miligraf
miligraf

Reputation: 1082

For the people coming here 2.5 years after this was asked, I was able to do this with Rails 3.2.13 and Ruby 1.9.3-p194:

result=ActiveRecord::Base.connection.select_all("SELECT id AS 'user_id', first_name AS 'name' FROM users LIMIT 1")
result.each do |row|
  row.each do |k, v|
    puts "column #{k} contains #{v}"
  end
end

Result:

column user_id contains 1
column name contains Me
[{"user_id"=>1, "name"=>"Me"}]

Access it:

result.first["user_id"]

And if there are 3 results and you want to get the 2nd one:

result[1]["user_id"]

Upvotes: 4

Steve Ross
Steve Ross

Reputation: 4144

Look up: MySQL/Ruby (http://www.tmtm.org/en/mysql/ruby/) if you're iterating a MySQL database. Other databases, look up the other drivers. Speaking purely about MySQL/Ruby, the result returned is a Mysql::Result.

You iterate this using each_hash and the block yields a hash for the row. You can then iterate the hash using each_pair. E.g.:

result = MyModel.connection.execute('select * from foos')
result.each_hash do |row|
  row.each_pair do |k, v|
    puts "column #{k} contains #{v}"
  end
end

Upvotes: 0

Related Questions