Обсуждение: Special characters in SQL queries
First a single quote in text, when a backforward slash in a file path, what other special characters need padded in two backslashes before using the data in a SQL statement? After hours' search in the PostgreSQL archive, I find a releted information on the http://www.ca.postgresql.org/users- lounge/docs/7.2/postgres/arrays.html. It's about array data though. How can I find out those characters so that I can pre-process them before a SQL query? Thanks for your information. Vernon
> > First a single quote in text, when a backforward slash in a file path, what other special characters need padded in t wo > backslashes before using the data in a SQL statement? > > After hours' search in the PostgreSQL archive, I find a releted information on the http://www.ca.postgresql.org/users - > lounge/docs/7.2/postgres/arrays.html. It's about array data though. > > How can I find out those characters so that I can pre-process them before a SQL query? > What about size_t PQescapeString (char *to, const char *from, size_t length); from the libpq - C Library? Regards, Christoph
Thank Christoph for your information. I don't program in C at all, but Java. Although I can make a way to call the C library function from Java, it isn't suitable solution, I believe. I only desire to find out all the type of characters at the present time so that I can strip out any potential problem sources in text. Who know what characters a user will enter. Vernon 11/03/2003 7:32:33 AM, Christoph Haller <ch@rodos.fzk.de> wrote: >> >> First a single quote in text, when a backforward slash in a file path, >what other special characters need padded in t >wo >> backslashes before using the data in a SQL statement? >> >> After hours' search in the PostgreSQL archive, I find a releted >information on the http://www.ca.postgresql.org/users >- >> lounge/docs/7.2/postgres/arrays.html. It's about array data though. >> >> How can I find out those characters so that I can pre-process them >before a SQL query? >> >What about >size_t PQescapeString (char *to, const char *from, size_t length); >from the libpq - C Library? > >Regards, Christoph > > >
* Vernon Wu <vernonw@gatewaytech.com> [12.03.2003 05:36]: > Thank Christoph for your information. > > I don't program in C at all, but Java. Although I can make a way to call the C library function from Java, it isn't suitable > solution, I believe. > > I only desire to find out all the type of characters at the present time so that I can strip out any potential problemsources > in text. Who know what characters a user will enter. > Take a look at the source code of PQescapeString() in the source distribution of postgres. I hope, you'll find all the chars you're interested in. > >> > >> First a single quote in text, when a backforward slash in a file path, > >what other special characters need padded in t > >wo > >> backslashes before using the data in a SQL statement? > >> > >> After hours' search in the PostgreSQL archive, I find a releted > >information on the http://www.ca.postgresql.org/users > >- > >> lounge/docs/7.2/postgres/arrays.html. It's about array data though. > >> > >> How can I find out those characters so that I can pre-process them > >before a SQL query? > >> > >What about > >size_t PQescapeString (char *to, const char *from, size_t length); -- Victor Yegorov
> > I don't program in C at all, but Java. Although I can make a way to call the C library function > from Java, it isn't suitable solution, I believe. > I only desire to find out all the type of characters at the present time so that I can strip out any > potential problem sources in text. Who know what characters a user will enter. > As Victor Yegorov mentioned Take a look at the source code of PQescapeString() in the source distribution of postgres. I hope, you'll find all the chars you're interested in. or refer to Binary Strings within the Data Types chapter of the doc. This shows how to deal with "non-printables" and "printables". Regards, Christoph
On Wednesday 12 Mar 2003 3:28 am, Vernon Wu wrote: > Thank Christoph for your information. > > I don't program in C at all, but Java. Although I can make a way to call > the C library function from Java, it isn't suitable solution, I believe. > > I only desire to find out all the type of characters at the present time so > that I can strip out any potential problem sources in text. Who know what > characters a user will enter. Don't do Java myself, but I can't believe the JDBC (or whatever) classes don't do this for you. In any case, you can look at the code for the C function - it should be fairly obvious what characters it's working on. If you do want to write your own, it's best not to strip certain characters, but rather to list those you will allow through. That way if you miss something it's a bug report rather than a security hole. -- Richard Huxton
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