Question

I’m trying to append content from a file to a string.

opening the file using iso-8859-1 encoding and setting the string to same encoding.

but when trying to concatenate values I get a incompatible character encodings: UTF-8 and ISO-8859-1 (Encoding::CompatibilityError) error.

why this happen if both strings are of same encoding?

actually I have no UTF-8 strings there.

sql = "
INSERT INTO pages
(meta_title, meta_description, meta_keywords, title, URL, content)
VALUES ('%s', '%s', '%s', '%s', '%s', '%s');
".force_encoding('iso-8859-1') # setting string to iso-8859-1

Dir['./*'].select { |e| File.file? e }.each do |e|
  f = File.open(e, "r:iso-8859-1") # opening the file using iso-8859-1
  # extracting meta, title etc
  puts sql % [*meta, title, url, content]
end

Answer 1

Try to use explicit encoding on extracted content as well.

Like this:

puts sql % [*meta, title, url, content].map { |s| s.force_encoding('iso-8859-1') }