module ActiveRecord::Sanitization::ClassMethods

# => "snake!_cased!_string"
sanitize_sql_like("snake_cased_string", "!")

# => "100!% true!!"
sanitize_sql_like("100% true!", "!")

# => "snake\\_cased\\_string"
sanitize_sql_like("snake_cased_string")

# => "100\\% true!"
sanitize_sql_like("100% true!")

occurrences of itself, "_" and "%".
LIKE statement. This method uses +escape_character+ to escape all
Sanitizes a +string+ so that it is safe to use within an SQL

def sanitize_sql_like(string, escape_character = "\\")
  pattern = Regexp.union(escape_character, "%", "_")
  string.gsub(pattern) { |x| [escape_character, x].join }
end