Pythian Group

The “Beer” version of DBD::Oracle (1.24) has been released. You can find it at CPAN DBD::Oracle.

DBD::Oracle is a Perl module that works with the DBI module to provide access to Oracle databases. It is maintained by me, John Scoles, under the auspices of Pythian as Open Source/Free Software.

This is largely a maintenance release that fixes a number of bugs. New stuff includes some more improvements to embedded types from Charles Jardine.

Timestamps in Embedded Object now use precision to 6 places.

The big enhancement this round is extending the code to allow more than one row to be returned with a single fetch. Those of you who use Rowcache size will now find that your queries will run much faster.

I have also added the ora_ncs_buff_mtpl parameter, so you can now have very fine grain control over the size of the data buffer using for NCHAR conversions of lobs.

One more little note — thanks to my mistake in compressing a file last week, the version number on CPAN is 1.24a, while the internal Version is still 1.24.

Here is the complete change list: Read the rest of this entry . . .

I finally had the opportunity the other day to try and install DBD::Oracle on an IBM AIX 5.1 box, and for once I have some good news to tell.

Anyone who has ever tried this will know of some of the troubles I speak of. When dealing with DBI and any DBD on a AIX box, you either must either be lucky enough to have the same compiler installed that built the version of Perl that comes with the box (I have never seen this happen); or you have to spend a great deal of time downloading and installing your own GCC and the building your own version of Perl.

Fortunately, all the hard work was done for me by other members of my team, and I was only a Johnny-come-lately to the whole process.

In our case, these are the steps that we followed:

1. get a working version of GCC on the box
2. rebuild and install your own version of Perl
3. build and install DBI using your local version of Perl

All of the above worked without a major problem. It was only when we tried to build DBD::Oracle that we ran into a problem:

Read the rest of this entry . . .

Thanks to a patch from Tomas Pokorny, you can now select Oracle user-defined types directly into a Perl object.

User-defined types include Object, Varray, and Table. These have been around in Oracle since 8i but have never really gained any sort of popularity for any number or reasons. The most common reason I have heard from DBAs and modelers is that they break relational integrity. As the objects in Oracle are “Embedded,” I do not see how that is possible. The more practical reason is that the SQL to retrieve and query this sort of object tends to be rather involved, and is sometimes slower than a simple table join; also, this sort of object can be hidden or unavailable to many kinds of modeling software.

With the new functionality of DBD::Oracle, selects of these objects are simple to work with in Perl. Lets take the example below for a web site that has a number of different “user” types. Read the rest of this entry . . .

The “Sesame Street” Version of DBD::Oracle (1.23) has been released.

You can find it at CPAN DBD::Oracle.

DBD::Oracle is the Perl module that works with the DBI module to provide access to Oracle databases. It is maintained by me, John Scoles, under the auspices of The Pythian Group as open source/free software.

This release is largely a maintenance release that fixes a number of bugs.

New stuff includes the ability to fetch Oracle embedded types directly into an oracle object; a big thank you goes out to Tomas Pokorny for that patch.

Also, UTF8 support has been expanded and cleaned up for BLOBs and execute_array and thanks go out to Milo van der Leij, David Mansfield for most of the work on this.

Also a big thanks Alex Buttery, Jim McCullars, Charles Jardine, Eric Simon, and Chris Underhill, who helped out with some clean up of the code, READMEs, and the POD.

I have also now added two private statement functions ora_stmt_type_name and ora_stmt_type which will get the OCI type name and type for the currently prepared statement.

The complete change list

Read the rest of this entry . . .

The latest release of DBD::Oracle is now ready and can be found at: CPAN DBD::Oracle. It is a Perl module that works with the DBI module to provide access to Oracle databases. It is maintained by me, John Scoles, under the auspices of The Pythian Group as open source/free software.

This release is largely a maintenance release that fixes a number of bugs (new and old) and cleans up the POD. I have also spent a good deal of time cleaning up the tests, compile warnings, and the Makefile.PL. A thank-you goes out to Martin Evans and H. Merijn Brand for their help on that.

As for new items, the ORA_VERBOSE attribute was added so that you can debug/trace DBD::Oracle without seeing any DBI debug/trace output. OCILobGetLength was added to the LOB functions, thanks to Milo van der Leij, I have also dropped support for Oracle 8 and earlier clients; see the POD for details on this.

Finally, I have also cleaned up and expanded how persistent LOBs work. A thank-you to Eric Simon for his work on this.

The release has been fully tested with version (1.601) of DBI. Below is the list of the changes and/or fixes in this release.

Read the rest of this entry . . .

1, 2, 3, 4, 5, 6, 9, or 10. It ain’t no Feist song, but she got it right. Notice that she mentions no 7 or 8 in it. Well, that is also true for version support in release 1.21 of DBD::Oracle.

With some of the new functionality that was introduced in DBD::Oracle 1.21, you can no longer use the Oracle 7 and most early 8 clients to build DBD::Oracle.

I hope this little table will help you choose which version of DBD::Oracle is right for you.

As there are dozens and dozens of different versions of Oracle’s clients, I did not bother to list any of them, just the major release versions of Oracle that are out there.

Note that one can still connect to any Oracle version with the older DBD::Oracle versions. The only problem you will have is that some of the newer OCI and Oracle features available in later DBD::Oracle releases will not be available to you.

So to make a short story a little longer:

Read the rest of this entry . . .

There seems to be a bug in DBD::Oracle’s execute_array when working with 11g.

If you tell DBD::Oracle to autocommit, it seems that in 11g this commit will not take place when an error occurs during the processing of one of the tuples that you passed into execute_array. So given this table:

CREATE TABLE test_array (
	    row_1 INTEGER NOT NULL,
	    row_2 INTEGER NOT NULL,
	    row_3 INTEGER NOT NULL)

the following code will result in no records being added to the db.

# create a database handle
my $dbh = DBI->connect('dbi:Oracle:','xxx@xxx','xx',{
	RaiseError			=> 1,
	PrintError			=> 0,
	ShowErrorStatement		=> 1,
	AutoCommit			=> 1

}) || die "Unable to establish connection with Oracle server: $DBI::errstr";

my $rv;
my @var1         = (1,1,1,1,1,1,1,1,1,1);
my @var2         = (2,2,2,2,'s',2,2,2,2,2);
my @var3         = (3,3,3,3,3,3,3,3,3,3);

my $tuple_status = [];
my $dumped ;
my $rows = [];

$sth->execute_array(
        {ArrayTupleStatus => $tuple_status},
          \@var1,
          \@var2,
          \@var2,
   );

The workaround is to set AutoCommit => 0 and then use $dbh-->commit() after the statement.

So far, the jury is out whether this is a bug only in 11g, but as this code works correctly in 9 and 10 (it adds the 9 rows), it seems likely. I have noted the bug here: http://forums.oracle.com/forums/thread.jspa?messageID=2663832#2663832.

Building High-Performance Drivers for Oracle Database 11g: OCI Tips and Tricks (PDF). I had the opportunity to have an early look at this white paper by Luxi Chidamdaram.

The paper goes over what needs to be done to use OCI effectively, especially in a web environment. The step-by-step approach taken in this document is very readable and the well explained code snippets make it a very good reference — great for comparing your code to the “proper” way to do it.

The novice OCI programmer will find the initial sections of great benefit, as it takes a lot of mystery out of OCI programming. For the more advanced OCI-head, the document is full of good examples of how to manage connections, sessions, and pooling–with an examination of what type of pooling is needed in a given situation.

One highlight for me was the section on database events, which are covered very effectively with some practical examples.

In short, this white paper is a must-read for both the OCI master and the novice, with some great pointers on how to use what is already in OCI and what is new in 11.

Karun Dutt and I managed to get DBD::Oracle 1.21 to install on a 64-bit Linux OS against the Oracle 11 full client. Here’s what we did.

As root, we downloaded DBD::Oracle from CPAN.

# perl -MCPAN -eshell
cpan> get DBD::Oracle
...

We replaced the distribution makefile with: http://svn.perl.org/modules/dbd-oracle/trunk/Makefile.PL (this is the latest Makefile.PL).

# cd /root/.cpan/build/DBD-Oracle-1.21
# export ORACLE_HOME=<actual value of Oracle Home>
# export ORACLE_SID=<actual value of ORACLE_SID>
# export ORACLE_USERID=<a working ORACLE_USERID>
# export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$ORACLE_HOME
# perl Makefile.PL
...
# make
...
# make test
...
# make install
...

It works!

I have just managed to get DBD::Oracle to successfully compile, install, and test with the 11.1.0.6.0 Instant Client (IC) on a Linux (32bit) OS. It seems Oracle, in its wisdom, has changed the folder structure yet again, so to get it to compile, try this.

The table structure of the IC out of the RPMs is:

/usr/lib/oracle/11.1.0.1/client/ (Instant Client Package Basic)
/usr/share/oracle/11.1.0.1/client/ (SQL*Plus)
/usr/include/oracle/11.1.0.1/client/ (Instant Client – SDK)

So, doing the following . . .

export ORACLE_HOME=/usr/lib/oracle/11.1.0.1/client
export PATH=$ORACLE_HOME/bin:$PATH
export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$PATH

perl Makefile.PL -m /usr/share/oracle/11.1.0.1/client/demo.mk -h /usr/include/oracle/11.1.0.1/client/

. . . will work.

I have also updated the Makefile.PL, which can be found here: http://svn.perl.org/modules/dbd-oracle/trunk/Makefile.PL.

Cheers, John Scoles.