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You could roll your own version of mysql_real_escape_string, (and improve upon it) with the following regular expression: [\000\010\011\012\015\032\042\047\134\140]. That takes care of the following characters: null, backspace, horizontal tab, new line, carriage return, substitute, double quote, single quote, backslash, grave accent. Backspace and horizontal tab are not supported by mysql_real_escape_string.