Re: ASCII Null control character validation

On 11/30/17 03:13, Alexey Chernyshov wrote:
> I found in src/backend/utils/mb/wchar.c: pg_verify_mbstr_len() that it
> reports ASCII Null character (\000) as invalid. As for me, it should
> pass validation. However, ASCII Null character breaks a line and the
> end of the line is missed, try:
>
> INSERT INTO mytable VALUES (E'a\001b\000c and rest of line MIA');
>
> Find patch attached. Am I wrong?

The main reason why you can't usefully have null characters in a string
literal is that the type input functions take a cstring as input, so no
string with a null character can possibly be input to a type.

So removing that check would just cause failure or confusion later.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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