Today, mysql_real_escape_string() is escaping single quotes AND double quotes

Question

$str = \'BEGIN This is a \"quote\" test. \\\'Single\\\' END\';
echo $str . \"\\n\";
echo mysql_real_escape_string($str);

// Outputs:
BEGIN This is a \"quote\" test.         


        

Answer 1

" does start a string in MySQL. (See: Strings)

Exception:

If the ANSI_QUOTES SQL mode is enabled, string literals can be quoted only within single quotation marks because a string quoted within double quotation marks is interpreted as an identifier.