NAME

ExtProc - Perl interface to the Oracle Perl External Procedure Library

SYNOPSIS

use ExtProc;

my $e = ExtProc->new;
my $dbh = $e->dbi_connect;
$e->ora_exception("error");

DESCRIPTION

The ExtProc module provides functions for interacting with the calling Oracle database from extproc_perl scripts.

FUNCTIONS

put_line(string)

Uses DBMS_OUTPUT.put_line to return output to the calling program (usually sqlplus). You must have enabled output from stored procedures ("set serveroutput" in sqlplus). You can also use the filehandle interface; see "fh" for details.

ep_debug(message)

If debugging is enabled, write the specified message to the debug log.

ora_exception(message)

Throws a user-defined Oracle exception. Note that the Perl subroutine will probably complete after this function is called, but no return values should be accepted by the calling client.

is_function()

Returns true if the subroutine is being called as a function.

is_procedure()

Returns true if the subroutine is being called as a procedure.

METHODS

new()

Returns an ExtProc object that can be used to call the methods below.

dbi_connect(\%attr)

Obtain a DBI handle for the calling database, with optional DBI attributes.

use DBI;
use ExtProc;

# get ExtProc object
my $e = ExtProc->new;

# connect back to the calling database
my $dbh = $e->dbi_connect();

# raise errors
my $dbh = $e->dbi_connect({RaiseError => 1});

NOTE: External procedures are stateless, so there is no concept of a persistent connection to the database. Therefore, you must call dbi_connect once per transaction.

fh()

Returns a filehandle that can be used for returning output to PL/SQL. You must have enabled output from stored procedures ("set serveroutput" in sqlplus).

use ExtProc;

sub testprint
{
   my $e = ExtProc->new;
   my $fh = $e->fh;
   print $fh "Hello world!";
}

SQL> set serveroutput on
SQL> exec Perl.proc('testprint')
Hello world!

register_destructor(coderef)

Register a destructor with extproc_perl to be called before the session exits. coderef should be a reference to a named or anonymous subroutine. Destructors are pushed onto a stack, and will be called in LIFO (last in, first out) order.

Destructors MUST exist prior to registration. Since no context exists between the database and external procedure during module unload, no attempt will be made to fetch the code from the database. In fact, destructors cannot access the database at all.

use ExtProc;

sub bye
{
   do_something();
}

my $e = ExtProc->new;
$e->register_destructor(\&bye);

AUTHOR

Jeff Horwitz <jeff@smashing.org>

SEE ALSO

perl(1), perlembed(1), DBI(3), DBD::Oracle(3)