Re: PL/SQL Function Calls

Mladen Gogala wrote:

> This is not really a problem because dynamic execution does not interact
> with the rest of the code. You have "execute immediate using" and that's
> that. That is one place where the execution takes place and not an "eval"
> type mechanism that you are asking for.

Don't understand your reasoning. PL/SQL allows you to make a dynamic call to static code and interact (via bind variables) with the code. PL/SQL allows you to create dynamic code and execute that.

> What does change the picture and where you were right and I was wrong are
> weak ref cursor variables. PL/SQL, unfortunately, cannot do anything like
> eval in Perl.

Not a Perl user myself, but if we're talking about standard eval functionality, then yes you can do it in PL/SQL. The following is in-line documentation from source code of an event system I wrote in PL/SQL. It takes any dynamic PL/SQL block that returns a boolean value, executes it and evaluates the result of the function.

• descr: This function executes an anonymous PL/SQL block as a
• boolean function --
• example:
• declare
• b$ boolean;
• begin
• b$ := ExecFunction( 'begin return(FALSE); end;' );
• end; --
• details:
• This function creates a dynamic anonymous PL/SQL code block that
• looks as follows:
• ==start==
• declare
• function DynamicFunction return boolean is
• begin
• << THE PL/SQL CODE BLOCK PASSED BY THE CALLER
• GOES HERE >>
• end;
• begin
• if DynamicFunction then
• :BOOLCHAR := 'T';
• else
• :BOOLCHAR := 'F';
• end if;
• end;
• ==end== --
• The function executes this using a bind variable called BOOLCHAR to
• determine the boolean result of the anonymous PL/SQL block. If then
• exits using the BOOLCHAR value - thus informing the caller whether
• the anonymous PL/SQL code block passed by the caller resulted in a
• TRUE or FALSE return.

PL/SQL is a formal programming language. And thus as capable as other formal programming languages. I think many sell PL/SQL short thinking of it ito "a macro for SQL".

--
Billy