Re: text column constraint, newbie question

On Sun, Mar 22, 2009 at 11:36 AM, RebeccaJ <rebeccaj(at)gmail(dot)com> wrote:
>> >  Are there characters, maybe non-printing characters, or perhaps
>> > even whole phrases, that could cause problems in my database or
>> > application if I were to allow users to enter them into that column?
>>
>> > If so, does anyone happen to have a regular expression handy that you
>> > think is a good choice for text columns' CHECK constraint? Or maybe a
>> > link to a discussion of this topic?
>>
>> Nope, there's nothing you can put into a text to break pgsql.
>> However, if you are using regular old queries, you'd be advised to use
>> pg_escape_string() function in php to prevent SQL injection attacks.
>
> Thanks! I'll check out pg_escape_string() in php, and I see that
> PostgreSQL also has something called PQescapeStringConn... I wonder if
> I should use both...

Isn't PGescapeStringConn a libpq function? I'm pretty sure that php's
pg_escape_string is just calling that for you, so no need to use both.

> Also, I should have asked: what about char and varchar fields? Can
> those also handle any characters, as long as I consider SQL injection
> attacks?

ayup. As long as they're legal for your encoding, they'll go right in.
If you wanna stuff in anything no matter the encoding, use a database
initialized for SQL_ASCII encoding.