Postgres-Konsole Randfall ignoriert POSIX-Regexp-Regeln?

[Canapin (Coin-coin le Canapin)]

I don’t know PostgreSQL, but it works using the rails console:

Post.find_each do |p|
  p.raw.gsub!(/"(.*?)"\:(http\S+?(?=\W+(?:$|\s))|http\S+)/, '[\\1](\\2)')
  p.save
end