Re: single quotation confusion

David Johnston <polobo@yahoo.com> wrote:
> R10 wrote

>> for example if a String txt = "it's cold" and to be inserted
>> into a sql query "insert into test values ('"+txt+"')";
>> it gives me
>> syntax error at or near "s"
>>
>> any ideas how to solve that problem ??
>
> In short you do not build queries by directly concatenating
> user-supplied data.  You use a PREPARED STATEMENT with
> placeholders and then use the setXXX methods to map the data.
>
> SQL: INSERT INTO test VALUES (?)

Yeah, David's suggestion is the way to go.  Trying to handle this
in an ad hoc fashion opens you to a class of attack known as "SQL
injection".  When concatenating without proper handling of quotes
(which drivers will do for you) you should consider yourself
*lucky* if the worst you have seen is errors.

http://xkcd.com/327/

The above link also illustrates why you shouldn't run the
application under a user ID which has permission to execute DML.

--
Kevin Grittner
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company