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Classic MetaLink vs. My Oracle Support

Jared Still - Thu, 2009-07-09 18:01
If you are in any way involved with supporting Oracle products, then you know that the death knell for Classic MetaLink has sounded. MetaLink will be unplugged at the end of July 2009.

The new support site, My Oracle Support, seems to be causing some pain for quite a few people in the Oracle user community.

Some of the complaints regard limited platform support due to the Adobe Flash 9 requirements, navigation and response times.

On the other hand there are some cool new features such as Power View, Configuration Manager and the new Advanced Search options.

How do you feel about it?

Here's a chance to let your opinion be know as a poll has been created where you can vote on it.

At this time 637 voters have voiced their opinion about MetaLink and My Oracle Support.

Current Poll results can be found in this Excel File: MetaLink vs My Oracle Support Results

Categories: DBA Blogs

Microsoft Deprecates OracleClient: Time to Consider Moving to ODP.NET

Christian Shay - Mon, 2009-07-06 22:52
Microsoft recently announced that it will deprecate Microsoft System.Data.OracleClient. For existing Microsoft OracleClient developers, especially those that haven't taken a look at the Oracle Data Provider for .NET (ODP.NET) in some time, this is a good time to look at ODP.NET again for new development or to migrate existing Oracle .NET applications. In recent years, ODP.NET has added lots of new features -- such as performance tuning, user-defined types, advanced queuing, RAC connection pooling, and supporting multiple ODP.NET client versions simultaneously on the same machine.

Alex Keh, who is the product manager for ODP.NET, has put together a special new webhome for developers using OracleClient...its called ODP.NET for Microsoft OracleClient Developers. This web page provides good information about why developers choose to migrate from ODP.NET from Microsoft OracleClient. Alex told me that the page will also provide a step-by-step Microsoft OracleClient to ODP.NET migration tutorial in the near future, which should be extremely useful. If you have questions about what this deprecation means for your company, please contact Alex over at alex.keh [at] oracle [dot] com or post to the ODP.NET Forum (OTN registration required).

In reading various comments on the MSDN post and elsewhere, I noticed a few misconceptions about ODP.NET that I would like to clarify:

Misconception: "This deprecation means I have to pay for an Oracle provider now!"
Fact: ODP.NET is free! You don't need to pay for a third party provider if you don't want to

Misconception: "I have to download a particular version of ODP.NET depending on the version of my database."
Fact: Any version of ODP.NET works with any version of Oracle Database. So you can use the latest version (currently and use it against a 9.2, 10, or 11g database!

Misconception: "I'll have to use the Oracle installer when I deploy my app. Argh!!!"
Fact: At deployment time, you don't have to use the Oracle installer to install ODP.NET if you don't want to. If you so choose you can write your own installer, using scripting or Installshield or whatever you want. All you need to do is download the XCOPY version of ODP.NET. As a bonus, it has a smaller footprint too!

Misconception: "If I need to standardize on/test different apps with different versions of ODP.NET I'm in big trouble!"
Fact:Multiple versions of ODP.NET can live on the same box and your application can target whatever specific one it was tested with. Not everyone has multiple apps that have been tested with different versions of ODP.NET but it happens.

Misconception: "I hit a bug in ODP.NET 9/ODP.NET 10! I can't use ODP.NET because of it!"
Fact: If you hit some nasty bug of some sort with ODP.NET 9 or even 10, make sure to download the 11.1 version and try it as the bug is likely fixed in the years that passed. Again, it does not matter what version of the database you are using, the 11g ODP.NET version will work against them all and over the years we have added tons of new features and bug fixes.

So again, please check out the ODP.NET for Microsoft OracleClient Developers webpage. I'll blog again when the migration step-by-step guide is posted there, so feel free to subscribe to my blog to get an alert when that happens!

Happy coding :)

Getting Started with OCCI (Windows Version)

Mark A. Williams - Mon, 2009-07-06 22:49

The Oracle C++ Call Interface, also known as OCCI, is an application programming interface (API) built upon the Oracle Call Interface (OCI - another lower level API from Oracle). One of the goals of OCCI is to offer C++ programmers easy access to Oracle Database in a fashion similar to what Java Database Connectivity (JDBC) affords Java developers. If you would like to learn more about what OCCI is (and isn't), pay a visit to the OCCI documentation on Oracle Technology Network (OTN) here:


My goal with this "Getting Started" post is to give you one method of setting up an environment in which you can use OCCI to develop C++ applications under Windows that access Oracle Database. I am not in any way covering all possible scenarios or delving deep into OCCI itself. Please note that the database itself can be on any supported host.

The Environment

Your environment is likely to differ from mine; however, it is important to be familiar with the various components in the environment used here so that you can make adaptations as necessary for your specific environment.

  • Oracle Database Server/Host: oel01 (Oracle Enterprise Linux 32-bit server)
  • Oracle Database: SID value of OEL11GR1, Service Name value of OEL11GR1.SAND, version
  • Development Machine: Hostname of CHEPSTOW, Windows XP Professional 32-bit
  • Development IDE: Microsoft Visual C++ 2008 Express Edition (Windows SDK also installed)
  • Oracle Client: Oracle Instant Client with OCCI
Important Information

One of the most crucial attributes of working with OCCI is that you must ensure that all of the components of the development environment and the runtime environment are supported combinations and correct versions. I can not emphasize this enough. If you deviate from this, you will almost certainly find trouble! In order to find the correct combinations of products and versions, see the following links on OTN:

Download the Correct Packages

At the time of this writing, the following are the component versions supported for the environment listed above:

  • OCCI (Visual C++9 (VS 2008)[Windows 32-bit])
  • Instant Client Version

From the download links above, you should download the following components to your development machine. I downloaded them to the C:\Temp directory.

  • OCCI (Visual C++9 (VS 2008)[Windows 32-bit]) - occivc9win32_111060.zip
  • Instant Client Package - Basic: instantclient-basic-win32-
  • Instant Client Package - SDK: instantclient-sdk-win32-
  • Instant Client Package - SQL*Plus: instantclient-sqlplus-win32-  (optional, but I always install it)
Install the Instant Client Packages

Installing the Instant Client packages is simply a matter of unzipping them – not much to wrong here! I unzipped them all to the C:\ directory on Chepstow. This resulted in a new top-level directory - C:\instantclient_11_1 with "sdk", "vc8", and "vc7" directories underneath. The "vc8" and "vc7" directories should be ignored in the context of the environment created here.

Install the OCCI Package

Much like the Instant Client packages, the OCCI package should be unzipped; however, rather than unzipping it to the C:\ directory, I unzipped it to the C:\Temp directory. Once unzipped, review the occivc9_111060_readme.txt file for information; however, I deviate from the directories listed in the file.

I create a "vc9" directory under the "sdk" directory as follows:


I create a "vc9" directory under the "instantclient_11_1" directory as follows:


I delete the oraocci11.dll and oraocci11.sym files from the C:\instantclient_11_1 directory. These files are not built/linked with the runtime libraries used by Visual Studio 2008 and, as mentioned above, it is critical that component versions match!

From the extracted OCCI files in the C:\Temp directory, move the following two files to the C:\instantclient_11_1\sdk\lib\msvc\vc9 directory previously created:

  • oraocci11.lib
  • oraocci11d.lib

From the extracted OCCI files in the C:\Temp directory, move the following four files to the C:\instantclient_11_1\vc9 directory previously created:

  • oraocci11.dll
  • oraocci11.dll.manifest
  • oraocci11d.dll
  • oraocci11d.dll.manifest

Finally, delete the oraocci11.lib file from the C:\instantclient_11_1\sdk\lib\msvc directory. Again, this file is not compatible with the environment created here.

After performing these steps, the .lib files should only be in directories under C:\instantclient_11_1\sdk\lib\msvc and the .dll and .manifest files should only be in directories under the C:\instantclient_11_1 directory. While this may seem like extra unneeded work, it results in complete separation of the various versions of the OCCI components making it easier (and explicit) which version is to be used.

To specify which version of the OCCI libraries are used, add the directory to the system path. You also add the the Instant Client directory to the path. Both of these directories should be added to the beginning of the system path:

C:\instantclient_11_1\vc9;C:\instantclient_11_1;{rest of path follows…}

Configure Visual Studio

The Windows environment has been configured to use the new OCCI and Instant Client packages but before you can begin developing in Visual Studio, you need to set a few options. Without these options Visual Studio will be unable to find the correct files and build your applications. There are two options that need to be specified:

  • Include files – allows Visual Studio to find the header files for OCCI
  • Library files – allows Visual Studio to find the library files for OCCI

Using Visual C++ 2008 Express Edition, the menu paths to specify these options are as follows:

  • Tools –> Options… Expand "Projects and Solutions" node, select "VC++ Directories", under "Show directories for:" select "Include files", double-click under the last entry to open a new box to enter a path, enter "C:\instantclient_11_1\sdk\include" and press enter
  • Under "Show directories for:" select "Library files", double-click under the last entry to open a new box to enter a path, enter "C:\instantclient_11_1\sdk\lib\msvc\vc9" and press enter
  • Click OK to save the settings
Create a Simple Test Project

All the setup work is now complete and the environment is configured! If needed, you can use the following (very!) basic application as a simple test to verify things are working as expected. Again, this is a simple example only to verify things are setup correctly. It is not intended to be a complete template for "proper" code development, etc.

Create the Visual C++ 2008 Express Edition project by selecting File –> New –> Project… from the main menu, select "Win32" as the project type, select "Win32 Console Application", give the project a name (I used OCCITest), select a location (I used C:\Projects), I unchecked "Create directory for solution", and then click OK.

Click Next in the Application Wizard, uncheck Precompiled header, click Empty project, and click Finish.

In Solution Explorer, right-click Header Files, select Add, select New Item…

In Add New Item, select Header File (.h), enter Employees.h (or any name you prefer) in Name, and click Add.

Here's the content of the file on my system:

* A simple OCCI test application
* This file contains the Employees class declaration

#include <occi.h>
#include <iostream>
#include <iomanip>

using namespace oracle::occi;
using namespace std;

class Employees {
  virtual ~Employees();

  void List();

  Environment *env;
  Connection  *con;

  string user;
  string passwd;
  string db;

In Solution Explorer, right-click Source Files, select Add, select New Item…

In Add New Item, select C++ File (.cpp), enter Employees.cpp (or any name you prefer) in Name, and click Add.

Here's the content of the file on my system:

* A simple OCCI test application
* This file contains the Employees class implementation

#include "Employees.h"

using namespace std;
using namespace oracle::occi;

int main (void)
   * create an instance of the Employees class,
   * invoke the List member, delete the instance,
   * and prompt to continue...

  Employees *pEmployees = new Employees();


  delete pEmployees;

  cout << "ENTER to continue...";


  return 0;

   * connect to the test database as the HR
   * sample user and use the EZCONNECT method
   * of specifying the connect string. Be sure
   * to adjust for your environment! The format
   * of the string is host:port/service_name


  user = "hr";
  passwd = "hr";
  db = "oel01:1521/OEL11GR1.SAND";

  env = Environment::createEnvironment(Environment::DEFAULT);

    con = env->createConnection(user, passwd, db);
  catch (SQLException& ex)
    cout << ex.getMessage();


  env->terminateConnection (con);

  Environment::terminateEnvironment (env);

void Employees::List()
   * simple test method to select data from
   * the employees table and display the results

  Statement *stmt = NULL;
  ResultSet *rs = NULL;
  string sql = "select employee_id, first_name, last_name " \
               "from employees order by last_name, first_name";

    stmt = con->createStatement(sql);
  catch (SQLException& ex)
    cout << ex.getMessage();

  if (stmt)

      rs = stmt->executeQuery();
    catch (SQLException& ex)
      cout << ex.getMessage();

    if (rs)
      cout << endl << setw(8) << left << "ID"
           << setw(22) << left << "FIRST NAME"
           << setw(27) << left << "LAST NAME"
           << endl;
      cout << setw(8) << left << "======"
           << setw(22) << left << "===================="
           << setw(27) << left << "========================="
           << endl;

      while (rs->next()) {
        cout << setw(8) << left << rs->getString(1)
             << setw(22) << left << (rs->isNull(2) ? "n/a" : rs->getString(2))
             << setw(27) << left << rs->getString(3)
             << endl;

      cout << endl;



Before you can build the sample, you need to add the OCCI library to the input list for the linker:

Select Project –> OCCITest Properties... from the menu (substitute your project name if different)

Expand Configuration Properties node, expand Linker node, select Input item, enter "oraocci11d.lib" for a debug build or "oraocci11.lib" for a release build.

Select Build –> Build Solution from the menu to build the solution. If everything is setup correctly, there should be no errors during the build. If you receive errors, investigate and correct them.

Executing the sample should result in output as follows:

ID      FIRST NAME            LAST NAME
======  ====================  =========================
174     Ellen                 Abel
166     Sundar                Ande
130     Mozhe                 Atkinson
105     David                 Austin
204     Hermann               Baer
116     Shelli                Baida
167     Amit                  Banda
172     Elizabeth             Bates

[ snip ]

120     Matthew               Weiss
200     Jennifer              Whalen
149     Eleni                 Zlotkey

ENTER to continue...

If you are new to using OCCI on Windows with Visual Studio, perhaps the above will be helpful in getting started!

ETL patent case: Constellar and DataMirror let off off the hook; DataStage still in dock

Nigel Thomas - Mon, 2009-07-06 14:27
Once again Vincent McBurney delivers a fantastic summary of the latest state of the Juxtacomm ETL patent case: SQL Server, DB2 and DataStage will fight out Data Integration Patent Infringement.

I'm most interested from the Constellar point of view - I first came across Constellar (then Information Junction) as a product on sale in late 1993 / early 1994 (before joining the company from Oracle in 1995), so it always seemed clear to me that it would qualify as prior art to Juxtacomm's 1998 patent. Oddly, it seems that the parties to the trial have agreed that Constellar Hub (and DataMirror Transformation Server) can be dropped from consideration; they won't be subject to damages - but equally they won't be considered as prior art. I don't understand that, but I guess the IBM lawyers must know what they are doing.

So, the case rumbles on, serving (if nothing else) to show how broken the US software patent system is.

SQLstream delivers instant data stream analysis of Mozilla 3.5 downloads

Nigel Thomas - Wed, 2009-07-01 13:52
Here are a couple of posts that describe the download monitor/dashboard which is giving up-to-the-second statistics for downloads by country of the latest Mozilla release 3.5 (just about to top 5.5 million downloads since yesterday's launch). The dashboard has been put together with the help of my friends at SQLstream. Just don't try looking at this with Internet Explorer, as it doesn't support HTML5.

Julian Hyde on Open Source OLAP. And stuff.: SQLstream powers ...
By Julian Hyde
SQLstream gathers data from Mozilla's download centers around the world, assigns each record a latitude and longitude, and summarizes the information in a continuously executing SQL query. Data is read with sub-second latencies, ...
Julian Hyde on Open Source OLAP.... - http://julianhyde.blogspot.com/
SQLstream the Sequel - RealTime Intelligence for Mozilla BI in Action
From ebizQ Presents BI in Action Virtual Conference ...

Introducing Oracle Team Productivity Center

Susan Duncan - Wed, 2009-07-01 09:22
Today is an exciting day for me. It's the launch of Oracle Fusion Middleware 11g in the USA and tomorrow the launch event comes to London. Included in this launch is, of course, Oracle JDeveloper 11gR1.

For some time I've been working on a new aspect of JDeveloper - Oracle Team Productivity Center. It is our first release of functionality to enable better Application Lifecycle Management for JDeveloper users and it is included in Oracle JDeveloper 11gR1.

TPC introduces the Team Navigator to JDeveloper. Through this navigator I can set up my team and user structure, applying team roles to users in teams/projects. I can connect to my existing ALM repositories and query/update artifacts in those repositories while working in JDeveloper.

In addition I can contextually link artifacts from different ALM repositories together - so I can create a relationship between a requirement defined in JIRA and a task in MS Project Server and I can tag items (needs a use case, ready for code review etc.) that are either visible to me or to all the members of my team. And I can be a member of multiple teams too. If I'm working on one task and am asked to switch to some other piece of code I can save the state of my development files open in the IDE against a specific work item. Work item is the generic term we give to any ALM artifact queried from an integrated ALM repository. So in the example below, I am working on a JIRA issue - SSTORE-23. If I Save Context I will save the Business Component files open in the editor along with the position and sizing of all the other JDeveloper windows. Then when I come back to this piece of work I can re-open SSTORE and Restore Context - to return my IDE to the saved state. Another great productivity booster!

A database is used to store queries, relationships, tags etc and managed by a small JEE application. This is set up by the installer and the client-side workings are downloaded through the normal Check For Updates Center in JDeveloper.

In this first release, in addition to the adaptors developed by us to connect to JIRA and MS Project Server I'm really pleased that we have partnered with Rally Software.

Rally is the leader in Agile application lifecycle management (ALM) dedicated to making distributed development organizations faster and leaner by dramatically cutting the time, cost and effort needed to deliver high quality applications. Rally's products were honored with four consecutive Jolt awards (the software industry's equivalent of the Oscar® award) in 2006, 2007, 2008 and 2009. The company's end-to-end solutions for Agile development also include Agile University, the largest source for Agile training, and Agile Commons, the largest collaborative Web 2.0 community dedicated to advancing software agility. Using the Rally Connector JDeveloper users can view and update their Rally tasks and defects directly from JDeveloper.

This release of TPC concentrates on enabling JDeveloper users, but Application Lifecycle Management is about more than just developers - it has a role in breaking down functional silos (development, QA, Doc, PM....) and it's our aim to push TPC out to more than developers going forward - both in terms of increased services provided by TPC and increasing the number of connectors available to differing ALM repositories (requirements, task, defects, testing etc)

One step towards that goal is the provision of a Connector Developers Guide and a sample connector to allow other third parties to create connectors to their existing ALM tools - be those commercial products or in-house systems.

But that's not all - JDeveloper users can also integrate their XMPP chat system into JDeveloper - even more productivity for developers without the need to leave their IDE! I can who of my team mates is connected to chat and also chat with all my buddies - whether they are working with TPC or not.

This is just a very brief introduction to Team Productivity Center. Browse the link above for more information, download, install and try it out - and let me know what you think ;-)

OTNs APEX Developer Competition 2009

Anthony Rayner - Wed, 2009-07-01 05:22
Are you the...

  ...travelling type?  Fancy winning a free ticket for Oracle OpenWorld in San Francisco (October 11 - 15) to meet with like minded APEX enthusiasts and learn more about APEX and other Oracle technology?

Or maybe more the...

  ...bragging type?  How would the words 'Oracle Application Express Developer Competition Winner 2009' look on your CV? It does have a certain ring to it, don't you think?

Or even the...

  ...academic type?   What about the prospect of furthering your understanding of APEX by paging through your winning copy of 'Pro Oracle Application Express'?

Whatever your reasons, enter the OTN 'Oracle Application Express Developer Competition 2009' by submitting an APEX application that stands out from the crowd and you could be in with the opportunity of winning one of these great prizes or accolades!

For more information, including submission guidelines, all important judging criteria and registration details, please visit the OTN page and David Peake's related post. Entries close 24 August, 2009.

Good luck!
Categories: Development

Approaches to "UPSERT"

Kenneth Downs - Mon, 2009-06-29 20:33

This week in the Database Programmer we look at something called an "UPSERT", the strange trick where an insert command may magically convert itself into an update if a row already exists with the provided key. This trick is very useful in a variety of cases. This week we will see its basic use, and next week we will see how the same idea can be used to materialize summary tables efficiently.


The idea behind an UPSERT is simple. The client issues an INSERT command. If a row already exists with the given primary key, then instead of throwing a key violation error, it takes the non-key values and updates the row.

This is one of those strange (and very unusual) cases where MySQL actually supports something you will not find in all of the other more mature databases. So if you are using MySQL, you do not need to do anything special to make an UPSERT. You just add the term "ON DUPLICATE KEY UPDATE" to the INSERT statement:

insert into table (a,c,b) values (1,2,3)
    on duplicate key update
     b = 2,
     c = 3

The MySQL command gives you the flexibility to specify different operation on UPDATE versus INSERT, but with that flexibility comes the requirement that the UPDATE clause completely restates the operation.

With the MySQL command there are also various considerations for AUTO_INCREMENT columns and multiple unique keys. You can read more at the MySQL page for the INSERT ... ON DUPLICATE KEY UPDATE feature.

A Note About MS SQL Server 2008

MS SQL Server introduced something like UPSERT in SQL Server 2008. It uses the MERGE command, which is a bit hairy, check it out in this nice tutorial.

Coding a Simpler UPSERT

Let us say that we want a simpler UPSERT, where you do not have to mess with SQL Server's MERGE or rewrite the entire command as in MySQL. This can be done with triggers.

To illustrate, consider a shopping cart with a natural key of ORDER_ID and SKU. I want simple application code that does not have to figure out if it needs to do an INSERT or UPDATE, and can always happily do INSERTs, knowing they will be converted to updates if the line is already there. In other words, I want simple application code that just keeps issuing commands like this:


We can accomplish this by a trigger. The trigger must occur before the action, and it must redirect the action to an UPDATE if necessary. Let us look at examples for MySQL, Postgres, and SQL Server.

A MySQL Trigger

Alas, MySQL giveth, and MySQL taketh away. You cannot code your own UPSERT in MySQL because of an extremely severe limitation in MySQL trigger rules. A MySQL trigger may not affect a row in a table different from the row originally affected by the command that fired the trigger. A MySQL trigger attempting to create a new row may not affect a different row.

Note: I may be wrong about this. This limitation has bitten me on several features that I would like to provide for MySQL. I am actually hoping this limitation will not apply for UPSERTs because the new row does not yet exist, but I have not had a chance yet to try.

A Postgres Trigger

The Postgres trigger example is pretty simple, hopefully the logic is self-explanatory. As with all code samples, I did this off the top of my head, you may need to fix a syntax error or two.

CREATE OR REPLACE FUNCTION orderlines_insert_before_F()
    result INTEGER; 
    -- Find out if there is a row
    result = (select count(*) from orderlines
                where order_id = new.order_id
                  and sku      = new.sku

    -- On the update branch, perform the update
    -- and then return NULL to prevent the 
    -- original insert from occurring
    IF result = 1 THEN
        UPDATE orderlines 
           SET qty = new.qty
         WHERE order_id = new.order_id
           AND sku      = new.sku;
        RETURN null;
    END IF;
    -- The default branch is to return "NEW" which
    -- causes the original INSERT to go forward
    RETURN new;


-- That extremely annoying second command you always
-- need for Postgres triggers.
CREATE TRIGGER orderlines_insert_before_T
   before insert
   EXECUTE PROCEDURE orderlines_insert_before_F();
A SQL Server Trigger

SQL Server BEFORE INSERT triggers are significantly different from Postgres triggers. First of all, they operate at the statement level, so that you have a set of new rows instead of just one. Secondly, the trigger must itself contain an explicit INSERT command, or the INSERT never happens. All of this means our SQL Server example is quite a bit more verbose.

The basic logic of the SQL Server example is the same as the Postgres, with two additional complications. First, we must use a CURSOR to loop through the incoming rows. Second, we must explicitly code the INSERT operation for the case where it occurs. But if you can see past the cruft we get for all of that, the SQL Server exmple is doing the same thing:

CREATE TRIGGER upsource_insert_before
ON orderlines
    DECLARE @new_order_id int;
    DECLARE @new_sku      varchar(15);
    DECLARE @new_qty      int;
    DECLARE @result       int;

    DECLARE trig_ins_orderlines CURSOR FOR 
            SELECT * FROM inserted;
    OPEN trig_ins_orderlines;

    FETCH NEXT FROM trig_ins_orderlines
     INTO @new_order_id

    WHILE @@Fetch_status = 0 
        -- Find out if there is a row now
        SET @result = (SELECT count(*) from orderlines
                        WHERE order_id = @new_order_id
                          AND sku      = @new_sku
        IF @result = 1 
            -- Since there is already a row, do an
            -- update
            UPDATE orderlines
               SET qty = @new_qty
             WHERE order_id = @new_order_id
               AND sku      = @new_sku;
            -- When there is no row, we insert it
            INSERT INTO orderlines 
            UPDATE orderlines

        -- Pull the next row
        FETCH NEXT FROM trig_ins_orderlines
         INTO @new_order_id

    END  -- Cursor iteration

    CLOSE trig_ins_orderlines;
    DEALLOCATE trig_ins_orderlines;

A Vague Uneasy Feeling

While the examples above are definitely cool and nifty, they ought to leave a certain nagging doubt in many programmers' minds. This doubt comes from the fact that an insert is not necessarily an insert anymore, which can lead to confusion. Just imagine the new programmer who has joined the team an is banging his head on his desk because he cannot figure out why his INSERTS are not working!

We can add a refinement to the process by making the function optional. Here is how we do it.

First, add a column to the ORDERLINES table called _UPSERT that is a char(1). Then modify the trigger so that the UPSERT behavior only occurs if the this column holds 'Y'. It is also extremely import to always set this value back to 'N' or NULL in the trigger, otherwise it will appear as 'Y' on subsequent INSERTS and it won't work properly.

So our new modified explicit upsert requires a SQL statement like this:


Our trigger code needs only a very slight modification. Here is the Postgres example, the SQL Server example should be very easy to update as well:

   ...trigger declration and definition above
   IF new._upsert = 'Y'
      result = (SELECT.....);
      _upsert = 'N';
      result = 0;
   END IF;
   ...rest of trigger is the same

The UPSERT feature gives us simplified code and fewer round trips to the server. Without the UPSERT there are times when the application may have to query the server to find out if a row exists, and then issue either an UPDATE or an INSERT. With the UPSERT, one round trip is eliminated, and the check occurs much more efficiently inside of the server itself.

The downside to UPSERTs is that they can be confusing if some type of explicit control is not put onto them such as the _UPSERT column.

Next week we will see a concept similar to UPSERT used to efficiently create summary tables.

Categories: Development

Debugging root cause of MQ related Errors

Ramkumar Menon - Mon, 2009-06-29 16:25

I ran into a few MQ errors. It helped me to take a look at $MQ_INSTALL_DIR\WebSphereMQ\Qmgrs\<QueueManagerName>\errors directory to see whats going on!

Oracle Pro*C on Windows with Express Edition Products

Mark A. Williams - Mon, 2009-06-29 10:34

NOTE: I have edited the intro text here from the original source as a result of some discussions I've had. These discussions are ongoing so I can't post the results as of yet. (3-June-2009 approximately 5:00 PM).

I thought I would take an introductory look at using the Oracle Pro*C precompiler using Express Edition products. Here are the components I will use for this purpose (links valid at time of posting):

  • Oracle Database 10g Express Edition (available here)
  • Oracle Enterprise Linux (available here)
  • Oracle Instant Client Packages for Microsoft Windows 32-bit (available here)
  •     Instant Client Package – Basic
  •     Instant Client Package – SDK
  •     Instant Client Package – Precompiler
  •     Instant Client Package - SQL*Plus
  • Microsoft Windows XP Professional 32-bit with Service Pack 3
  • Microsoft Visual C++ 2008 Express Edition (available here)
  • Windows SDK for Windows Server 2008 and .NET Framework 3.5 (available here)

For the purposes of this discussion you will need to have already installed (or have access to) Oracle Database with the HR sample schema. You will also need to have installed Visual C++ 2008 Express Edition and the Windows SDK on the machine you will use as your development machine. For a walkthrough of installing Visual C++ 2008 Express Edition and the Windows SDK, please see this link. Note that even though the SDK seems to be only for Windows Server 2008 (based on the name) it is supported on XP, Vista, and Windows Server.

In my environment I have installed Oracle Database 10g Express Edition on a host running Oracle Enterprise Linux. The host name is "oel02" (not especially clever, I realize). The Windows XP machine that I will use as the development machine is named "chepstow" (perhaps marginally more clever) and Visual C++ Express Edition and the Windows SDK are already installed. I have downloaded the four Instant Client packages listed above to the "c:\temp" directory on chepstow. The SQL*Plus package is not required; however, I find it convenient so I always install it. So, since I already have a database server and the Microsoft tools are installed, all that remains is to install the Instant Client packages.

Installing the Instant Client Packages

It is incredibly easy to install the Instant Client packages – simply unzip them! I chose to unzip them (on chepstow, my development machine) to the "c:\" directory and this created a new "c:\instantclient_11_1" directory and various sub-directories. I then added the following two directories to the system path:

  • C:\instantclient_11_1
  • C:\instantclient_11_1\sdk

NOTE: I added the two directories to the beginning of the system path and had no other Oracle products installed. See comments for more information about this. (Added 29 June 2009 approximately 11:30 AM)

Setting up the Pro*C Configuration File

I know it is easy to skip reading a README file, but it is important that you do read the PRECOMP_README file in the Instant Client root directory. Pro*C will, by default, look for a configuration file named "pcscfg.cfg" when it is invoked. In the environment that I have created (default installs of all products) Pro*C will want to find this file in the "c:\instantclient_11_1\precomp\admin" directory. However, if you look at your install (if you have done the same as me) you will notice there is no such directory! Therefore you should create this directory ("c:\instantclient_11_1\precomp\admin"). You should then copy the "pcscfg.cfg" file from the "c:\instantclient_11_1\sdk\demo" directory to the "c:\instantclient_11_1\precomp\admin" directory.

The "pcscfg.cfg" file will initially contain the following single line:


Below this line you add the following four lines:


Save the file and exit your editor.

Be sure to note that the directory names above are the "short" names to ensure they do not contain spaces. If the directory names contain spaces this will cause problems with the Pro*C precompiler. To help "translate" the directories above, here are the long versions (be sure you do not enter these):

sys_include=C:\Program Files\Microsoft Visual Studio 9.0\VC\include\sys
include=C:\Program Files\Microsoft SDKs\Windows\v6.1\Include
include=C:\Program Files\Microsoft Visual Studio 9.0\VC\include

You can find the short names by using "dir /x" in a command-prompt window.

Adding Directories to Visual Studio C++ 2008 Express Edition

Next you should add the Oracle Instant Client include and library directories to Visual Studio. To do this, simply perform the following steps:

  • Select Tools –> Options to open the Options dialog
  • Expand the "Projects and Solutions" node
  • Click the "VC++ Directories" item
  • Under "Show directories for:" select "Include files"
  • Click underneath the last entry in the list (you should get a highlighted line with no text)
  • Click the folder button to create a new line
  • Enter "c:\instantclient_11_1\sdk\include" and press Enter
  • Under "Show directories for:" select "Library files"
  • Click underneath the last entry in the list (you should get a highlighted line with no text)
  • Click the folder button to create a new line
  • Enter "c:\instantclient_11_1\sdk\lib\msvc" and press Enter
  • Click the OK button to save the changes
Create a New Project

WARNING: You should create your project in a directory (and path) that has no spaces in it. If you create the project in a directory or path with spaces you will receive errors during the precompile phase. I used "c:\temp" for this example.

Now create a new project in Visual Studio:

  • Select File –> New Project to open the New Project dialog
  • Select "Win32" as the project type
  • Select "Win32 Console Application" under "Templates"
  • Give the project a name (I used "proctest" in keeping with my clever naming tradition)
  • I always choose to de-select "Create directory for solution" and click OK
  • Click the "Next" button in the application wizard
  • Click the "Empty project" checkbox under "Additional options"
  • Click the "Finish" button
Create the Pro*C Source File

To create the Pro*C source file, perform the following steps:

  • Right-click "Source Files" and select Add –> New Item… from the context menu
  • Select "Code" under "Visual C++"
  • Select "C++ File (.cpp)" under "Visual Studio installed templates" (note that you will not actually create C++ code in this example)
  • Give the file a name such as "proctest.pc" and click "Add"

Here's the Pro*C source I used for this example (this is clearly sample code and lots is left out!):

** suppress certain warnings
#ifdef WIN32

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sqlca.h>
#include <sqlda.h>
#include <sqlcpr.h>


** defines for VARCHAR lengths.
#define UNAME_LEN 30
#define PWD_LEN   30
#define DB_LEN    48
#define FNAME_LEN 32
#define LNAME_LEN 32

** variables for the connection
VARCHAR password[PWD_LEN];

** variables to hold the results
int ctr;
int empid;


** declare error handling function
void sql_error(char *msg)
  char err_msg[128];
  size_t buf_len, msg_len;


  printf("\n%s\n", msg);
  buf_len = sizeof (err_msg);
  sqlglm(err_msg, &buf_len, &msg_len);
  printf("%.*s\n", msg_len, err_msg);



void main()
  ** Copy the username into the VARCHAR.
  strncpy((char *) username.arr, "hr", UNAME_LEN);
  username.len = strlen("hr");
  username.arr[username.len] = '\0';

  ** Copy the password.
  strncpy((char *) password.arr, "hr", PWD_LEN);
  password.len = strlen("hr");
  password.arr[password.len] = '\0';

  ** copy the dbname (using EZCONNECT syntax)
  strncpy((char *) dbname.arr, "oel02/XE", DB_LEN);
  dbname.len = strlen("oel02/XE");
  dbname.arr[dbname.len] = '\0';

  ** register sql_error() as the error handler.
  EXEC SQL WHENEVER SQLERROR DO sql_error("ORACLE error--\n");

  ** Connect to database.  Will call sql_error()
  ** if an error occurs when connecting.
  EXEC SQL CONNECT :username IDENTIFIED BY :password USING :dbname;

  printf("\nConnected to ORACLE as user: %s\n\n", username.arr);

  ** simple select statement
    SELECT   employee_id,
    FROM     employees
    ORDER BY last_name,

  ** open the cursor

  ** when done fetching break out of the for loop

  ** simple counter variable
  ctr = 0;

  ** print a little header
  printf("Employee ID  First Name            Last Name\n");
  printf("===========  ====================  =========================\n");

  ** fetch all the rows
  for (;;)
    EXEC SQL FETCH emps into :empid, :fname, :lname;

    ** null-terminate the string values
    fname.arr[fname.len] = '\0';
    lname.arr[lname.len] = '\0';

    ** print the current values
    printf("%-13d%-22s%-25s\n", empid, fname.arr, lname.arr);


  ** close the cursor

  ** provide simple feedback on how many rows fetched
  printf("\nFetched %d employees.\n", ctr);

  ** disconnect from database

  ** have a nice day

  Add a Reference to the Generated C Source File

The output of the Pro*C precompiler is either C or C++ source code (C in this case). However, because we are working with only a Pro*C source file we need to tell Visual Studio about the file that will be generated. To do this we add a reference to the not yet generated file:

  • Select Project –> Add New Item to open the Add New Item dialog
  • Select "Code" under "Visual C++"
  • Select "C++ File (.cpp)" under "Visual Studio installed templates"
  • Type "proctest.c" in the "Name" textbox and click "Add"
  • Next close the (empty) file after it is created
Add the Pro*C Library File to the Project
  • Select Project –> <project name> Properties… to open the Property Pages dialog
  • Expand the "Configuration Properties" node
  • Expand the "Linker" node
  • Click the "Input" item
  • In the "Additional Dependencies" type "orasql11.lib" and click "OK" to save the changes
Add the Custom Build Step

In order for Visual Studio to be able to invoke the Pro*C executable (proc.exe) to create the C source code file, a custom build step needs to be created:

  • Right-click "proctest.pc" in the Solution Explorer and select "Properties" from the context menu
  • Select "Custom Build Step"
  • For "Command Line" type "proc.exe $(ProjectDir)$(InputName).pc"
  • For "Outputs" type "$(ProjectDir)$(InputName).c"
  • Click "OK" to save the custom build step

This step will cause Visual Studio to invoke proc.exe on the input file (proctest.pc) and create an output file called "proctest.c" which will then be compiled as normal. This is really the key step in the whole process I suppose. This custom build step is the "integration" of Pro*C into Visual Studio.

Build the Sample and Verify

All the hard work is now done and it is time to build the sample!

  • Select Build –> Build Solution

If all has gone well you should see output similar to the following in the output window:

proctest - 0 error(s), 0 warning(s)
========== Build: 1 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========

If there are errors reported you will need to investigate and correct the cause.

Upon completion of a successful build, you can execute the program and verify the results:


Connected to ORACLE as user: hr

Employee ID  First Name            Last Name
===========  ====================  =========================
174          Ellen                 Abel
166          Sundar                Ande
130          Mozhe                 Atkinson

[ snip ]

120          Matthew               Weiss
200          Jennifer              Whalen
149          Eleni                 Zlotkey

Fetched 107 employees.



Whew! That's a lot of work! As I mentioned at the beginning of this post, this is intended to be an introductory look at using Pro*C and Visual C++ 2008 Express Edition. There is, of course, much more that Pro*C can do and this simple example of selecting from the "employees" table in the "hr" schema is exactly that: a simple example. It is not intended to be a complete tutorial but perhaps it will be helpful in working with Pro*C and Visual Studio if you choose to do so. You should be able to adapt the steps here to using the "full" version of Visual Studio or Oracle Client.

If you made it this far, thanks for stopping by. I hope this was helpful in some regard.


NOTE: Some comments below were recently deleted by me at the request of the poster. I have, therefore, deleted my responses to those comments as they made no sense on their own. (1-June-2009 approximately 1:10 PM)

One more date trick

Klein Denkraam - Mon, 2009-06-29 04:11

Tyler Muth has a useful addition to the date functions I have published here before.

If you ever want to know how long ago a date is and you want to display it in ‘human readable’ format you (and I) could use his function.

Like this:

select date_text_format(sysdate - 3/86400) the_date from dual;
select date_text_format(sysdate - 5/1440) the_date from dual;
select date_text_format(sysdate - 1/24) the_date from dual;
select date_text_format(sysdate - 3.141549) the_date from dual;
select date_text_format(sysdate - 15) the_date from dual;
select date_text_format(sysdate - 120) the_date from dual;
select date_text_format(sysdate - 365) the_date from dual;
3 seconds ago
5 minutes ago
1 hour ago
3 days ago
2 weeks ago
4 months ago
1 year ago

One more for the toolbox.

Are you sure you will be able to activate your standby??

Fairlie Rego - Sun, 2009-06-28 06:50
A couple of weeks I faced a scenario where the standby database crashed

On looking at the alert.log I see the following message in the alert.log of the standby

Sat Jun 6 06:48:52 2009
Recovery interrupted!
cannot find needed online log for redo thread 1
Some recovered datafiles maybe left media fuzzy
Media recovery may continue but open resetlogs may fail
Sat Jun 6 06:48:53 2009
Errors in file /u01/app/oracle/admin/TEST/bdump/test1_mrp0_24533.trc:
ORA-10576: Give up restoring recovered datafiles to consistent state: some error occurred
ORA-16037: user requested cancel of managed recovery operation
Some recovered datafiles maybe left media fuzzy
Media recovery may continue but open resetlogs may fail
Sat Jun 6 06:48:54 2009
Waiting for MRP0 pid 24533 to terminate

Hmmm... this means that if the standby does not have the redo and cannot get it from the primary you will not be able to online media fuzzy files using supported methods

The same issue is explained in Bug 5956646
as an architectural limitation.

This is a very unlikely scenario but a possibility none the less

Concepts Guide: 5/27 - Schema Objects

Charles Schultz - Wed, 2009-06-24 15:16
I found that reading the Guide is quite hard if you are already tired. ;-)

As always, I like pictures. Figure 5-1 on page 5-3 does justice. Although they would make their point more clear by labelling the schemas.

Was not aware of intra-block chaining (pp 5-5) - interesting concept. Especially since it does not affect performance (does not increase the number of IO calls).

Figure 5-3 is good in that it really helps to see the various pieces of a block and the row, including the headers.

As much as I hate how nulls are handled in Oracle, the one good thing is that I like how Oracle just does not even record information for null-trailing rows (ie, column-length not stored in block). Except, of course, if you have LONG data - DO NOT USE LONG! =)

I was not aware how table compression actually worked. Now that I know a little more about it, I am surprised the guide did not mention any limitations. For example, if a block has 100% unique data (uncompressable), would the symbol table still be built and populated? If not, what is the cut-off? At what point does Oracle deem compression worthwhile, pragamatically?

I have never seen a practical use for nested tables, but I'll keep my eyes open. I jumped to 27-7 as referenced just to see what it said. I still have never seen a practical use for nested tables.

The fact that sessions are "bound" to temp tables was new to me; I did not realize you could not do ddl on a temp table if is already bound to a session. Kinda makes sense, though. I wonder why they do not simply call it "locking"? =) Afterall, that is how normal tables are handled.

Ojbect Views really confuse me, not being familiar with the concept. And this being the Concepts Guide, I found that the short little blurb did not really help me much at all.

I also did not realize that one could put declaritive constraints on views; interesting way to propagate metadata information for restricted environments.

The short paragraph on Materialized View Logs did not do the concept any justice. I get the impression that either space and/or time was restrained when this section was done. =)

The intro section to Dimensions left my head whirling. I am not a Warehousing guy by any means; while I appreciate the extra background and the quasi-example, I find that it deep-dives too quick for me. And using an example of a year being tied to a year-row is just the most absurd thing I have ever heard. Why not a practical, real-life example that "anyone" can grasp?

Good discussion for sequences; I like how the good is balanced with the bad - the "Caution" is stronger than I expected, but I think very important and am glad to see that the authors made it stand out.

Nice long section on indexes. *grin* I always find it strange to find in 10g documentation references to "analyze table", when most of the time I believe they really mean collect stats, for which we are told to use dbms_stats instead. The intro to deterministic (user-defined) indexes was quite interesting. I would personally consider this an example of "black magic" in Oracle. Another one of those cases where there is a strong lack of practical examples.

Figure 5-7 starts out looking like a great pictoral example. However I found it to be quite confusing. Actually, what I really want to see is how an index is built, starting with one row. At the very least, it would be helpful to augment the figure with text explaining the function of the values for the branch blocks. However, excellent information on how searches are mathematically bounded (big-O notation).

Excellent piece on bitmap indexes; great examples, wonderful discourse. I appreciate the balanced approach to addressing the pros and cons of bitmap indexes, which may at the outset seem to be the pancea of query performance issues. The sidebar on cardinality was very well done as well.

The section on Index-organized tables was also quite interesting, however I wonder why, if they are so highly recommended for OLTP applications, why are they not more popular?

Application Domain indexes, and the Oracle Data Cartridge in general, are another area of black magic that I fear ever going back to. I dabbled in it once when attempting to define custom statistics for a function and never looked back. =) I am sure they have their place on some "True Expert"'s shelf, but not here....

Like IOTs, the Concepts Guide does a good job selling Clusters and Hash Clusters as beneficial methods, but I do not see many folks using it in Real Life. Is it merely the learning curve that keeps the standard DBA away from these features? We have a lot of third-party apps; shall we assume that the vendors simply do not have the expertise to utilize these fun but advanced toys?

Interesting stuff none-the-less.

(Integrity) Constraints in a datawarehouse

Klein Denkraam - Wed, 2009-06-24 02:51

In data warehouse land it is not very common to see constraints in the database. I never felt very comfortable with that, but until now I did not get around to analysing why I felt that way. Until I read this article by Tom Kyte. In the article Tom Kyte shows that the CBO (Cost Based Optimizer) can profit from the information that is derived from the presence of constraints by generating better query plans. Better in this case is defined as ‘producing result sets faster’. The examples in the article are not exactly ‘real world’ data warehouse examples. Following Tom Kyte’s line of reasoning I do agree that constraints are capable of improving the performance of queries.

The reasons for not having constraints in a data warehouse are along the lines of ‘I have checked the integrity when I did my ETL, so why would I need constraints to confirm that? And besides, constraints would only delay my ETL because they have to be checked before they are really enabled’. I see a couple of flaws in this reasoning:

  • I suspect that most constraints in a data warehouse cannot be enabled when actually applied. The quality of the ETL might be good, but is it just as good as a constraint would be? I think not.
  • Enabling constraints might take time, but how often do you have to check constraints? Only when doing the ETL, of course. I hope that in your DWH, doing ETL will be during a small part of the time your DWH is being used. Otherwise your DWH will have a problem. The rest of the time your DWH will be used for querying and Tom Kyte just showed that querying can be sped up by applying constraints.

Summing up my pros and cons of applying constraints.


  • it will improve the data quality of the DWH
  • it can speed up the queries in your DWH (querying it is the purpose of your DWH anyway)


  • it will take more time to do your ETL (which is only a means to create your DWH)

My conclusion is that I wil try to incorporate as many constraints as possible in my next DWH. It also means I will have to be smart enough to enable the constraints at just the right moment during my ETL to have an acceptable loading performance.

The Humble PL/SQL Exception (Part 1a) - The Structure of Stored Subprograms

Tahiti Views - Sun, 2009-06-21 23:52
As I said in my previous post, The Humble PL/SQL Exception (Part 1) - The Disappearing RETURN, there are a lot of nuances surrounding exception handling. That post attracted some comments that I thought deserved a followup post rather than just another comment in response.oraclenerd said (excerpted):I'm going to have to disagree with you on the internal procedure (in the declaration section) John Russellhttp://www.blogger.com/profile/17089970732272081637noreply@blogger.com1

Microsoft To Deprecate System.Data.OracleClient

Mark A. Williams - Fri, 2009-06-19 10:10
I found the following to be an interesting announcement:

System.Data.OracleClient Update

It looks like Microsoft have decided to deprecate System.Data.OracleClient beginning with the .NET 4.0 release.

Of course, I'm more than a little biased when it comes to anything related to Oracle.

For more information and to download ODP.NET, please see the Oracle Data Provider for .NET center on Oracle Technology Network (OTN).

opatch problem on Windows

Yasin Baskan - Fri, 2009-06-19 08:30
There is a note in Metalink that explains that on Windows having space characters in your ORACLE_HOME variable, the patch location or JDK location causes an error when running opatch. Yesterday I saw a strange problem that is similar to the above case.

If your opatch directory contains space characters you get a strange error. Even if the above conditions were not present we got an error like this:

C:\Documents and Settings\test\Desktop\OPatch>opatch lsinventory
Exception in thread "main" java.lang.NoClassDefFoundError: and

OPatch failed with error code = 1

Metalink returns no results for this error. This error is caused by the space characters in "Documents and Settings". When you move the opatch directory to another directory which does not contain space in its name opatch runs without this problem.

Just a note to help in case someone gets the same error.


Yasin Baskan - Fri, 2009-06-19 05:32
Yesterday I attended Kevin Closson's Exadata technical deep dive webcast series part 4. It is now available to download here. In there he talks about DBFS which is a filesystem on top of the Oracle database which can store normal files like text files. DBFS is provided with Exadata and is used to store staging files for the ETL/ELT process. This looks very promising, he sites several tests he conducted and gives performance numbers too. Watch the webcast if you haven't yet.

The Extra Hurdle for Marketing Through Social Media: You Gotta Make 'em Feel

Ken Pulverman - Thu, 2009-06-18 20:47

So we've been chatting recently with a vendor, Corporate Visions. They follow the

approach that a message that sticks is one that's wrapped in emotion. It's amazing to see when this technique is executed well. This video that a friend pointed me to is not new new, in fact 150k plus people have already seen it. But I think the folks at Grasshopper.com (actually the agency they hired) really nailed this approach.

It's interesting to note how intertwined the notion of making a message stick, something good salespeople have known how to do forever, and our expectations associated with new and social media.

Clearly we all want to feel something, and we all have very high expectations of social media in this regard. I think this notion is perhaps an extension of my last post, The Importance of Being Earnest.

So....I now have a request.

Please add comments to this blog with links to messages that you think were made to stick - messages wrapped in emotion. I wanna see what you got.

Go ahead, try to make me cry.... or laugh. Actually, I have a strong preference for laughing.

The Humble PL/SQL Exception (Part 1) - The Disappearing RETURN

Tahiti Views - Thu, 2009-06-18 00:59
Exception handling in PL/SQL is a big subject, with a lot of nuances. Still, you have to start somewhere. Let's take one simple use case for exceptions, and see if it leads to some thoughts about best practices. (Hopefully, this is not the last post in this particular series.)One common pattern I find in PL/SQL procedures is a series of tests early on...if not_supposed_to_even_be_here() then John Russellhttp://www.blogger.com/profile/17089970732272081637noreply@blogger.com2


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