Question

1)

require 'sqlite3'

db = SQLite3::Database.new('development.sqlite3')
db.results_as_hash = true;


rows = db.execute(" SELECT * FROM listings WHERE name = '' OR telephone = '' OR latitude = '' OR longitude = '' ")

rows do |row|

  id_num = row['id']
  puts "Id = #{id_num}"

  dupe_name = row['name']
  puts "name = #{dupe_name}"

  dupe_tel = row['telephone']
  puts "tel = #{dupe_tel}"

  dupe_lat = row['latitude']
  puts "lat = #{dupe_lat}" 

  dupe_long = row['longitude']
  puts "lat = #{dupe_long}" 
  puts '===end===='



end

2)

    require 'sqlite3'

db = SQLite3::Database.new('development.sqlite3')
db.results_as_hash = true;


db.execute(" SELECT * FROM listings WHERE name = '' OR telephone = '' OR latitude = '' OR longitude = '' ") do |row|

  id_num = row['id']
  puts "Id = #{id_num}"

  dupe_name = row['name']
  puts "name = #{dupe_name}"

  dupe_tel = row['telephone']
  puts "tel = #{dupe_tel}"

  dupe_lat = row['latitude']
  puts "lat = #{dupe_lat}" 

  dupe_long = row['longitude']
  puts "lat = #{dupe_long}" 
  puts '===end===='



end

The 2nd one works and the 1st one does not.

Why is that so? Doesn’t the db.execute function return a result set. If so why cant you loop through it?

Answer 1

Have you tried changing rows do |row| to rows.each do |row| for the first function?.

With the first one you get a collection and assign it to rows. You need to create a iterator for rows after that to loop trough the collection.

The second function, .execute already returns a iterator.

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