Oracle added a "procedural" component, otherwise know as PL/SQL, to the Oracle Relational Database Management System a long time ago. With a programming language in the database engine, application developers can work with database objects in their native form with significant improvements in efficiency and scalability.

I can not claim to know everything there is to know about PL/SQL and significant changes happen from version to version that make it even more difficult to keep up. This web log is my attempt to document some of the things I have learned over the years and to report on "new" (at least to me) discoveries as I come across them.

Feedback and suggestions are always appreciated. E-mail me at JohnJeunnette at PrairieSystemsGroup dot com.


UTL_FILE and BLOB data (No comments yet. Click the title to add one.)
Keywords: BLOB , UTL_FILE
I have been moving documents out of the database with a Java procedure for quite awhile but discovered today that the Oracle 11 Express Edition does not include a JVM (Java Virtual Machine). So, after a bit of research I discovered that the UTL_FILE package can handle binary data. (Actually, the feature has been around since version 9i...). Some example code: DECLARE -- this_file utl_file.file_type; l_buffer raw(32767); l_amount binary_integer := 32767; l_pos number := 1; l_blob blob; l_blob_len number; out_path (set the path to a directory in the utl_file_dir initialization parameter) out_name varchar2(200) := null; -- BEGIN -- for document_record in ( select blob_content from ) loop out_name := (build a meaningful file name) -- l_blob_len := dbms_lob.getlength(document_record.blob_content); -- this_file := utl_file.fopen( out_path, out_name,'wb',32767); -- while l_pos < l_blob_len loop, l_amount, l_pos, l_buffer); utl_file.put_raw(l_file, l_buffer, true); l_pos := l_pos + l_amount; end loop; -- utl_file.fclose(l_file); -- end loop; -- END;

ODTUG Tool Survey (3 comments. Click the title to review or add one.)
Keywords: Oracle Tools , ODTUG

We have assisted ODTUG with an (almost) annual survey of developers for several years.

The latest and greatest analysis of the 2010 survey is available now: ODTUG_Tool_Trends_article.pdf.

Comments and/or suggestions are appreciated.


The PL/SQL Web Toolkit (No comments yet. Click the title to add one.)
Keywords: PL/SQL Web Toolkit
It is only appropriate that I start this web log with some comments on the PL/SQL Web Toolkit. I have been using the toolkit for something like ten years now to create a number of database-based web applications. I still marvel at the simplicity and power of the concept of letting a browser-based HTML page communicate directly with the database, and vice-versa.

Some site examples include this web site content management application (Max), a technical conference abstract and registration processing application (CAAT at, a resource reservation tool (RRT at, and even a recipe storage site (ORB at

Operationally, the PL/SQL Web Toolkit is an Apache web server "mod", called mod_plsql, that takes HTTP requests from the browser and hands them off to a procedure in the database. The database procedure generates HTML and sends it back to the mod_plsql which returns the HTTP response to the browser. I'll expand on the use and abuse of the PL/SQL Web Toolkit in future columns.

Another area we will focus on is the collection of system packages that come with the database. PL/SQL code is the mechanism to operate the various options so we will spend some time on how to use the system packages.

Stay tuned for occasional thoughts.


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