New in Oracle 12c: Querying an Associative Array in PL/SQL Programs

I was aware that up to Oracle 11g, a PL/SQL program wasn’t allowed use an associative array in a SQL statement. This is what happens when I try to do it.

SQL> drop table test_array purge;

Table dropped.

SQL> create table test_array as
  2  select level num_col from dual
  3  connect by level <= 10;

Table created.

SQL> select * from test_array;


10  (more...)

Are You Using BULK COLLECT and FORALL for Bulk Processing Yet?

Steven Feuerstein was dismayed when he found in a PL/SQL procedure a cursor FOR loop that contained an INSERT and an UPDATE statements.

That is a classic anti-pattern, a general pattern of coding that should be avoided. It should be avoided because the inserts and updates are changing the tables on a row-by-row basis, which maximizes the number of context switches (between SQL and PL/SQL) and consequently greatly slows the performance of the code. Fortunately, (more...)

Case sensitivities and making JavaScript more like PL/SQL

Yesterday the Anti-Kyte (a.k.a. Mike) published a great post on coding styles. I started to post a comment but ended up rambling to I thought I'd put my thoughts here.

I can't be one to comment on tangential intros (just look at any of my presentations), but he almost lost me when I thought the entire post was going to be soccer jokes I didn't get but switched in time to three controversial (more...)

The APEX_JSON package: Generating JSON from PL/SQL

In my previous blog post, I took a look at the new APEX_JSON package that ships with Apex 5.0 and its capabilities for parsing JSON.

In this blog post, I am going to look at how the APEX_JSON package can be used to generate JSON from data in your database using PL/SQL.

There are multiple ways of creating JSON output using the APEX_JSON package. There are several overloaded write() procedures which can output (more...)

The APEX_JSON package: Parsing JSON in PL/SQL

As I mentioned a year ago, it looks like Apex 5.0 will include a new package called APEX_JSON for parsing and generating JSON. In this blog post, I will take a quick look at the parsing, and the next blog post will be about generating JSON output.

Since Apex 5.0 is still in Early Adopter (beta) mode and not yet released for download, we can run a query against the data dictionary (more...)

Creating PDF reports from PL/SQL

Do you need to create PDF reports from PL/SQL?

There are a number of options:

  • Anton Scheffer wrote a PL/SQL package called AS_PDF3 that covers all the basics: Different fonts (including TrueType), images, and tables.
  • There's the commercial PL/PDF package that has more features, such as the ability to use existing PDF documents as templates for new documents, compression, encryption, and more. There's also an extra Toolkit component which allows you to extract pages from (more...)

Some things to share…

I have been awfully quiet on my blog lately. I think that is because I have been busy with other things, like my garden and stuff like that. There are some ‘techie’ thing I have done in the meantime, though,

Tech14-Ive_SubmittedI have submitted a couple of abstracts for Tech14. Hope at least one of them gets selected. I really like presenting and if it is in a different country, that is just a plus. That (more...)

PL/SQL oddity

sokrates@12.1 > create procedure p is begin null; end this_does_not_compile;
  2  /

Warning: Procedure created with compilation errors.

sokrates@12.1 > show errors
Errors for PROCEDURE P:

-------- -----------------------------------------------------------------
1/32	 PLS-00113: END identifier 'THIS_DOES_NOT_COMPILE' must match 'P'
	 at line 1, column 11

sokrates@12.1 > REM expexted
sokrates@12.1 > create function f return number is begin return null; end this_does_not_compile;
  2  /

Warning: Function created with compilation errors.

sokrates@12.1 >  (more...)

Current_Schema and the Data Dictionary

Being a huge fan of Logger, the PL/SQL logging utility, I really wanted this be to included in the project that I'm currently working on. So I downloaded it (link at the bottom of this blog) and included it in our deployment scripts. Done.... at least I thought so, but of course this wasn't the case.

The regular install script for Logger looks something like the following (parts removed and table names are changed):

set (more...)


plsql_logoThere is a ‘rule’, I think it was created by Tom Kyte, stating: If you can do it in SQL, do it in SQL. I came across some code the other day that makes perfect sense to do then you are running an Oracle 10g (or earlier) instance. I rewrote the code to use only the EMP and DEPT tables to protect the suspects and maybe innocent.

The function defined is something like this:

Oracle PL/SQL Programming 6th edition by Steven Feuerstein

opp6_catI have reviewed the latest edition of Oracle PL/SQL Programming. This is not a book, at least for me, that I would read front to back. I use it mostly as a reference, but the great thing about this book is that you can also use this book to learn programming PL/SQL from scratch.

The book is nicely ordered into different parts, like Program structure and how to use SQL in PL/SQL (which by the (more...)

PL/SQL, UTL_HTTP and Digest Authentication

For the first time in what seems like ages, I've actually put together a piece of code worth sharing. It's not that I haven't been working, but just that it has all been very 'in-house' specific.

However I had a recent requirement to use a web service that makes use of Digest Authentication. If you have look at the UTL_HTTP SET_AUTHENTICATION subprogram, it only addresses Basic authentication (and, apparently, Amazon S3 which looks intriguing).

In (more...)


After a presentation by Lucas Jellema I decided to try something with types in Oracletable_EMP. One of the issues posed in this presentation was that the type cannot include self-reference. Neither direct nor indirect.

A table like the emp table cannot be expressed as an object type. The table has a column mgr which is a reference to another employee.

So I tried something like this:




This year, from June 22 - June 26, the best convention in the world, ODTUG’s KScope14 will be held in Seattle, Washington. I am already looking forward to meeting some ‘old’ friends again, creating new friends and seeing some of the best content by presenters from all over the world.

Some of the presentations I am looking forward to:

In the Developer’s Toolkit track:

Readable Code for Modify_Snapshot_Settings

It annoyed me slightly that when I googled modify_snapshot_settings just now and all of the examples used huge numbers for the retention with (at best) a brief comment saying what the number meant. Here is a better example with slightly more readable code. Hope a few people down the road (more...)

Invisible Not Null Column

Yesterday I attended John King (@royaltwit) session on Oracle 12c for developers. He gave an overview of all the goodies that are available to us as developers. The whole plugging and unplugging of database, though very cool and exiting, is most likely not very relevant to most developers.
When he (more...)

APEX Tree based on Pipelined Table Function

Representing hierarchical data in an APEX Tree is fairly straight forward, the wizard to create a tree region assists you with that. But when you need to show data from multiple tables, you will need to provide your own query. In a previous blogpost I have written how to achieve (more...)

Oracle Database 12c PRAGMA UDF and WITH clause enhancements

Here are two interesting enhancements in Oracle database 12c PL/SQL. PL/SQL subprogram defined using WITH clause of a subquery – Oracle database 12c allows PL/SQL declaration section in the WITH clause. One can define PL/SQL function or procedure into a WITH clause. Functions declared in the PL/SQL declaration section can (more...)

New York Oracle User Group Fall Conference Materials

Thank you all who attended my sessions at NYOUG Fall Conference this morning. I appreciate spending you most precious commodity - your time - with me. I sincerely hope you found both the presentations enlightening as well as entertaining.

Please see the details of the sessions below along with the (more...)

Oracle 12c OFFSET…FETCH.. bug?

Working on the chapter that covers best ways of manipulating with object collection. Of course, if you talk about pagination of the rowset, it is very tempting to test Oracle 12c new feature - OFFSET…FETCH.

Unfortunately, immediately got an issue. It seems to me that passing a variable to FETCH (more...)