Re: LIKE predicate and '\' character

Andy Hallam wrote:
>
> > I sent a previous mail with regard to using the '\' (backslash) character
> in
> > an SQL SELECT statement.
> > The outcome was that postgres does not escape the '\' itself - I need to
> do
> > it myself before submitting the SQL - fair enough, I now do this.
>
> I have just written a java app that uses a single '\' in an SQL SELECT
> statement and unlike my C application that uses the PSQLODBC driver this
> *DOES* return data. To me this says that the problem of having to escape the
> '\' myself (as I have to do in my C++ ODBC application) has already been
> addressed in the Java driver, and so I do not need to escape it myself in my
> Java application.
> If this problem has been addressed in the Java driver then surely (for
> conformity) it should also be addressed in the ODBC driver ?.

Doesn't psqlodbc driver work as you expect either if you
use a parameter binding ?

regards,
Hiroshi Inoue
>
> Here is my Java code :
> ...
>         try {
>                 con = DriverManager.getConnection(url, "postgres",
> "postgres");
>         }
>         catch (Exception e) {
>             MyOutput(e.getMessage());
>             System.exit(1);
>         }
>
>         try {
>            String strPart;
>
>             strPart = "A\\B";
> MyOutput("strPart: <" + strPart + ">");
>
>             strSQL = "SELECT partdesc FROM partmaster WHERE partnum = ?";
> MyOutput("SELECT SQL: <" + strSQL + ">");
>
>             PreparedStatement pstmt = con.prepareStatement(strSQL);
>             pstmt.setString(1, strPart);
>
>             result = pstmt.executeQuery();
>
>             while (result.next()) {
>                 data = result.getString(1);
> MyOutput("DATA FETCHED: Partdesc = <" + result.getString(1) + ">");
>             }
>         }
>         catch (Exception e) {
>             MyOutput(e.getMessage());
>             System.exit(1);
>         }
>
> Here is my program output:
>
> strPart: <A\B>
> SELECT SQL: <SELECT partdesc FROM partmaster WHERE partnum = ?>
> DATA FETCHED: Partdesc = <AB SLASH TEST>
>
> Java does have the same problem with the LIKE predicate however, as to
> return any data I need to change my code to :
>
> ...
> strPart = "A\\\\B";
> ...
> strSQL = "SELECT partdesc FROM partmaster WHERE partnum LIKE ?";
>
> Comments please.
>
> Andy
> ahm@exel.co.uk
>
> "Andy Hallam" <ahm@exel.co.uk> wrote in message
> news:9sb3ek$r0k$1@news.tht.net...
> > PostgreSQL - 7.1.3  (installed on Linux 2.4.2-2)
> > PSQLODBC.DLL - 07.01.0007
> > Visual C++ - 6.0
> >
> > I sent a previous mail with regard to using the '\' (backslash) character
> in
> > an SQL SELECT statement.
> > The outcome was that postgres does not escape the '\' itself - I need to
> do
> > it myself before submitting the SQL - fair enough, I now do this.
> >
> > i.e
> > instead of
> >     mydb=# SELECT * FROM users WHERE id = 'WORKGROUP\me';
> > I now do
> >     mydb=# SELECT * FROM users WHERE id = 'WORKGROUP\\me';
> >
> > BUT, if I use the LIKE predicate I have to escape the escape.
> >
> > i.e
> >     mydb=# SELECT * FROM users WHERE id LIKE 'WORKGROUP\\\\me';
> >
> >
> > Now this must be treated as a bug.
> > As you can see it is not an error with the PSQLODBC driver as I ran the
> SQL
> > from the command line with the same results.
> > I am presuming that the backend parsing logic around the LIKE prodicate is
> > ignoring the '\'.
> >
> > Is anyone working on this ?. Can anyone send me a fix, as without this I'm
> > screwed.
> >
> > Thanks for any help
> >
> > Andy.
> > ahm@exel.co.uk
> >
> >
> >
>
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