Re: Quick SQL expression evaluation

[Charles Wilt <charles.wilt@xxxxxxxxx>]

Not going to work as static SQL, dynamic SQL to the rescue...

     d wSqlStmt        s            100a   varying
     d wResults        s             10i 0
      /free

         wSqlStmt = 'values 2+2 into ?';
         exec sql
           prepare myStmt from :wSqlStmt;

         exec sql
           execute myStmt using :wResults;

         dsply %char(wResults);

         *INLR = *ON;
         return;
      /end-free

HTH,
Charles


On Tue, May 25, 2010 at 8:30 AM, Dennis Lovelady <iseries@xxxxxxxxxxxx> wrote:
> I am trying to write a procedure I thought would be extremely simple: a
> short SQL evaluation program that would simply take an expression and return
> the result of SQL operating on that expression.  For a silly example:
>
> Exec sql set :myResult   = 2 + 2 ;
>
>
>
> To minimize complexity, I am passing the '2 + 2' part as a string, so that
> the meat of this very short procedure is:
>
> Exec sql setl :myResult = :myExpression ;
>
>
>
> But (and, yes, I know I should have expected this) SQL is seeing it as the
> string "2 + 2" rather than a pair of values with an operator between them.
> Is there an SQL verb/clause that informs the SQL processor that the
> following is an expression rather than a string (such as with unix' "expr"
> command)?  Or is this just a pipe dream, not worth the effort?
>
>
>
> Dennis E. Lovelady
> AIM/Skype: delovelady      MSN: fastcounter@xxxxxxxxxxxx
>  <http://www.linkedin.com/in/dennislovelady>
> www.linkedin.com/in/dennislovelady --
> You can't have everything.  Where would you put it?
>
>
>
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