Lost or grayed out icons in Discoverer Plus

I have been researching the issue over lost or grayed icons and it is definitely an issue with Java memory on the local PC. So far, my research indicates that you need to increase the Java heap memory. I am still researching but here is what I have so far:

You may want to alter the maximum memory heap value for your Java. To do this, use this workflow:

1. From the Start button, use Settings > Control Panel.
2. Double-click Java Plug-in .
3. On the Advanced tab, set the Java Runtime Parameters to something like:
   –Xmx256m
4. Click Apply .

This sets the maximum amount of memory to allocate to Java to be 256 Mb. The installed default is 64 Mb which in my opinion is way too low. You can alter the maximum (-Xmx) to other values if you have plenty of memory but 256m seems to work very well. Generally I would not set the maximum to be more than 25% of your system memory. Initial research indicates that as a by-product you may find Plus loads and executes worksheets a little quicker also.

You may also want to increase the cache allowed for your local Java. The default is 50 MB but because the Plus applet takes almost 75% of this to even load, I recommend increasing this to 500 MB.

To alter the cache to 500 Mb, use this workflow:

1. From the Start button, use Settings > Control Panel.
2. Double-click Java Plug-in.
3. On the Cache tab, set the Maximum to 500 MB
4. Click Apply .

You can also increase the cache this way:

1. From the Start button, use Settings > Control Panel.
2. Double-click Java Plug-in.
3. On the Advanced tab, add another Java Runtime Parameter like this:
   -Dcache.size=100m
4. Click Apply .

If you have been experiencing issues with icons graying out, please let me know how you get on and whether the above helps. If you have made some alternative settings or know of another workaround please let me know what settings you applied. If you also notice any improvement in performance please let me know too.

10g Discoverer Handbook - Page 923 (Do not upgrade Java)

On page 923 of the Oracle Discoverer 10g Handbook I state and show you how to disable the automatic update feature that comes with the Sun JRE. Here is a before and after screenshot showing what can happen if you mistakenly leave the update enabled.

In this before screenshot, with Sun 1.4.2_06 installed, you can see that the drop-down correctly displays the current value.
However, in the following screenshot, taken following the upgrade to JRE 1.5, you can clearly see that the current value is grayed out.

To disable the automatic upgrade of the Sun JRE, use this workflow:

1. From the Windows Start menu, select Settings > Control Panel.
2. Double-click the icon for the Java ™ Control Page. It is usually named either Java or Java Plug-in.
3. When the Java Control Panel opens, click the Update tab.
4. Uncheck the box labeled "Check for updates automatically".
5. Click OK to save and exit.

Note: if your system has already upgraded to Sun JRE 1.5 or above you will need to remove the old Java and re-install the one.

To remove the Sun JRE 1.5 and re-install the correct version, use this workflow:

1. From the Windows Start menu, select Settings > Control Panel.
2. Double-click Add or Remove Programs.
3. Locate and remove the Java runtime environment.
4. Depending upon which version your Application Server is using, download the Sun JRE 1.4.2_04 or 1.4.2_06 software from the Sun website. They can be found here:
   http://java.sun.com/products/archive/j2se/1.4.2_04/index.html
   http://java.sun.com/products/archive/j2se/1.4.2_06/index.html
5. On this page, look for and click on the Download J2RE link.
6. On the next page, you are required to read and accept the license agreement.
7. After checking the box labeled "Accept License Agreement", download the software labeled "Windows Offline Installation, Multi-Language". This file is about 15Mb in size.
   Either you or one of your IT staff should now connect to your machine as a local administrator and install the software. The Application Server will recognize that the software has already been installed and will not try to install it again, thus allowing Plus to run.

The file that is downloaded is an executable, and is called either: jr2e-1_4_2_04-windows-i586-p.exe or 1_4_2_06-windows-i586-p.exe

NULL format display when upgrading to 10.1.2

It seems that when you upgrade from a previous version of Discoverer to 10.1.2 that the existing default setting for null values has changed from blank to the word NULL. This is annoying because it means that the default display for null values in 10.1.2 is not the same as it was in previous releases. What this means is that old workbooks that contain null values will now display the word NULL instead of blank. One of my customers reported this to Oracle as a service request and received the following reply:

You will need to open each and every workbook, make the change and resave. There is no global setting to apply for previously created and saved workbooks unfortunately.Hope the above information was informative. If this answers your question kindly close the TAR else feel free to update the TAR.

My customer has 100s of workbooks and it will take some time to go through this. I pity the person who has 1000s of workbooks because they will have to do this for each and every one! Don't be fooled into thinking that what you set in pref.txt will help because it won't. The upgrade is done using Discoverer Administrator which does not even know of the existence of pref.txt so it will ignore whatever you have set and will use its own default which is NULL.

If anyone knows of a workaround please let me know. Otherwise, if you have encountered this issue yourself please share your experience.

Best Presentation - ODTUG 2005

This week I have been at the ODTUG (link)Kaleidoscope 2006 conference at the Wardman Park hotel in Washington DC, and what a nice hotel it is. The reason I am here was to take part in the business intelligence summit that was organized by Oracle. My paper, The art of using calculations in Discoverer had been accepted by the ODTUG conference as one of the papers that would be included within the BI Summit (list of papers in summit). I presented my paper on Monday afternoon, the first afternoon of the conference, to a very attentive and receptive audience.

You can imagine my surprise when I arrived last Sunday to find that last year's paper, A first look at Discoverer 10g Release 2, had been nominated as one of the top 10 papers for the 2005 conference. Actually, the authors of the top 10 papers read like a who's who of the cream of Oracle presenters: Mike Ault (link), Bradley Brown (2 papers) (link), Don Burleson (2 papers) (link), Tony Catalano, Paul Dorsey (2 papers) and Steve Feuerstein (link). Then there was me.

Tuesday lunchtime came and the excitement had been building because the previous day the committee had said that they would be announcing the winners of the two coveted speaker awards - Best Speaker and Best Presentation, during lunch. I am delighted to be able to tell you that yours truly won the award for the best presentation with my old friend Tony Catalano, from TUSC, winning the award for the best speaker. We were both shocked because seeing the power of the authors that were against us we were convinced that we were there only to make up the numbers. My award, which incidentally is a rather beautiful black plaque with gold lettering, reads as follows:

Oracle Development Tools User Group
Best Presentation Content and Topic
Michael Armstrong-Smith
Armstrong-Smith Consulting
A First View of Discoverer 10g Release 2
ODTUG 2005
New Orleans, Lousiana

On Wednesday I will be delivering an encore of the winning presentation, a copy of which can be found on the download page of our main website (link). Some photographs were taken and just as soon as I am able to get my hands on one or two I will post here. As you can tell, I am thrilled to bits. It still hasn't 100% sunk in.

I have to say though that I would not have won this award without the help of my dear wife Darlene. She not only contributed to the paper but was the co-presenter of the presentation with me in New Orleans. So even though there is room for only one name on the award, it really was a team effort and she deserves as much credit for this award as I do. Thanks sweetheart, without you I would not be where I am today.

Unable to save a workbook to the database

One of my clients recently had an issue with Discoverer 10.1.2 in that every time a user tried to save a workbook to the database they got the following error:

ORA-1483 INVALID LENGTH FOR DATE OR NUMBER

Upon further investigation it was noted that they were using 10.1.0.4 version of the database and that the database was installed onto a HP-UX(PA-RSIC) 64 bit server.

According to Oracle, there is a known bug, number 3668164, within the 10.1.0.4 database that will prevent Discoverer from being able to save to the database. SAVING A WORKBOOK USING DISCOVERER 10G GIVES - ORA-1483. I have to admit that I had not heard of this bug and so my interest was aroused. Upon further investigation it turns out that the operating system is a red herring and that this issue can arise on any operating system.

The solution is to patch the database to 10.1.0.5 or higher. Apparently there is a one-off patch for 3668164 but not if your database is running on a Windows server. In this case you will have to apply the full 10.1.0.5 database upgrade. My recommendation though is to upgrade to 10.1.0.5 anyway as many other bugs were fixed in this release.

Postscript: my client informed me that after they upgraded their database that the issue went away.

Note: bug 3668164 is not available for public viewing. This is most frustrating because Oracle have lots of cross references to it on MetaLink.