File deleted each time

I have a ruby controller

def new
    counter = 1
    fileW = File.new("query_output.txt", "w") 
    file = File.new("query_data.txt", "r")
    while (line = file.gets)
        puts "#{counter}: #{line}"
        query = "select name,highway from planet_osm_line where name ilike '" +line+"'"
        @output = PlanetOsmLine.connection.execute(query)   
        @output.each do |output|
            fileW.write(output['highway'] + "\n")
        end
        counter = counter + 1
    end
    file.close
    query = ""
   @output = PlanetOsmLine.connection.execute(query)
 end

So in this I am reading from a file like

    %12th%main%
    %100 feet%
    %12th%main%
    %12th%main%
    %12th%main%
    %100 feet%

In the ruby console I can see all the queries getting executed but in query_output.txt I only get the output of last query. What am I doing wrong here?