Symptoms and Oracle 10g R2 for Windows

Yesterday I sounded like Barry White, today I can’t speak, much to the delight of my co-workers. I feel fine, but when I talk nothing comes out. Perhaps I should write all this text with a white font on a white background to simulate my current situation.

This reminds me of a summer holiday during University, when I worked on a production line in a factory for 3 months. All but one of the guys I worked with were deaf, and the one guy that could hear was at the other end of the line so I never got to speak to him. Fortunately the guys were really good at lip reading, so for 3 months I talked at work mostly without making any sound. I remember having a “chat” in the canteen one lunchtime and I started to speak out loud and got some funny looks from some of the guys off another line. It was only then I realized they had assumed I was deaf to as they had never heard me speak out loud 🙂

I had to teach a class last night using the “do as I do” method. Thought I would save my voice. Fat lot of good that did me!

I’ve just noticed that a Developers Release of Oracle Database 10g Release 2 (10.2.0.1.0) for Microsoft Windows is available for download. Not sure what’s missing from this, but it’s not a fully supported production release like the Linux version.

Cheers

Tim…

Bits and bobs…

David Aldridge’s blog contains links to a couple of handy Firefox search extensions here. Thanks to all involved. I’m making good use of them.

Howard Rogers made reference to Desktop ASM in one of his recent answers on the Dizwell Forum. Sounds like it’s worth a play. I haven’t managed to play with ASM very much. We made the transition from 9i RAC to 10g RAC really early and at the time there was very little to suggest that ASM had been used in anger. As a result we made the decision to avoid it, which on reflection was a pity.

I’m feeling a little under the weather this week. On Monday my nose was blocked. On Tuesday I felt fine. On Wednesday my throat was a little sore. Today I woke up sounding like Barry White (should have recorded an album), but now I sound normal and my nose is dodgy again. I have no idea what is going on. Let’s see what the symptoms tomorrow brings.

Isn’t it great when two separate members of the team, in this case a developer and yours truly, are independently asked to solve a problem and come up with the same solution. The question is, do we have equally good or equally bad solutions? I guess both 🙂

Cheers

Tim…

New article, weird experience and film review…

New article
I wrote a quick how-to article about Renaming or Moving Oracle Files in response to a forum thread. Nothing new and exciting here for those in the know, but it might help some of the newer people.

Weird experience
I had a bit of an weird experience last night. I finished quite a tough Karate class and didn’t feel particularly like socializing so I went to the cinema on my own to watch “The Descent”. I’d been meaning to see it for a couple of weeks, but never got round to it. I was feeling pretty thirsty so I bought one of those stupidly large cups (more like buckets) of diet Coke. I sat down to watch the film and started drinking at a pace. Within about ten minutes of the film starting I had the shakes bigtime! I was shivering uncontrollably and felt really bad. I guess the fact I was so tired and had just downed a bucket of ice-cold diet coke had caused my core temperature to drop quite quickly.

I wasn’t totally sure what to do, my judgment was a little off as you can imagine, but fortunately my natural reaction was to start using Ujjayi breath. This is a special type of loud breathing (like Darth Vader) used in Ashtanga Yoga to help generate heat. Sounds a bit dumb, but within five minutes I was feeling a lot better. So much so I was able to watch the film…

Film review – The Descent
Take a bunch of athletic and overly adventurous young women with an assortment of issues and send them caving. Next, have them make some stupid decisions and for good measure throw in some subterranean predators.

Unknown to me I’ve become claustrophobic in my old age. I can’t remember really having a problem with this before, but there are several scenes where people are in really confined spaces that made me want to freak out. I know these scenes were included to increase the tension, but they were by far the scariest bits of the film for me!

There are the usual gore and “make you jump” scenes that you would expect from a horror film. Several of the latter made everyone in the cinema scream, then bust out laughing.

Despite the unfortunate episode at the start of the film I really enjoyed it. It’s not a high budget film, so don’t expect perfect effects, but it’s a significant step forward compared the director’s previous film “Dog Soldiers”. I liked that too, but it is a seriously low budget film 🙂

Cheers

Tim…

Note to self. If you’re ever invited to go caving make a polite excuse and run for your life!

The curse of the Tru64 port…

I’ve said it before and I’ll say it again, Oracle products don’t run properly on Tru64 anymore!

The latest issue came from an observation by a developer and involves problems with using NVL inside an EXISTS subquery. The following code is the test case I sent in my TAR to Oracle support.

CREATE TABLE tab1 (
code         VARCHAR2(10),
description  VARCHAR2(50)
);

ALTER TABLE tab1 ADD (
CONSTRAINT tab1_pk PRIMARY KEY (code)
);

INSERT INTO tab1 (code, description) VALUES ('1', 'ONE');
INSERT INTO tab1 (code, description) VALUES ('2', 'TWO');
INSERT INTO tab1 (code, description) VALUES ('3', 'THREE');

CREATE TABLE tab2 (
code         VARCHAR2(10),
tab1_code    VARCHAR2(10),
description  VARCHAR2(50)
);

ALTER TABLE tab2 ADD (
CONSTRAINT tab2_pk PRIMARY KEY (code)
);

ALTER TABLE tab2 ADD (
CONSTRAINT tab2_tab1_fk FOREIGN KEY (tab1_code)
REFERENCES tab1(code)
);

CREATE INDEX tab2_tab1_fk_i ON tab2(tab1_code);

INSERT INTO tab2 (code, tab1_code, description) VALUES ('1', '1', 'ONE');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('2', '1', 'ONE');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('3', '1', 'ONE');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('4', '2', 'TWO');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('5', '2', 'TWO');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('6', '2', 'TWO');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('7', '3', 'THREE');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('8', '3', 'THREE');
INSERT INTO tab2 (code, tab1_code, description) VALUES ('9', '3', 'THREE');

COMMIT;

VARIABLE p1 VARCHAR2(1)
BEGIN
:p1 := '%';
END;
/

SELECT t1.code
FROM   tab1 t1
WHERE  EXISTS(SELECT rowid
FROM   tab2 t2
WHERE  t2.tab1_code = t1.code
AND    t2.code like :p1)
ORDER BY t1.code;

CODE
----------
1
2
3

3 rows selected.

SELECT t1.code
FROM   tab1 t1
WHERE  EXISTS(SELECT rowid
FROM   tab2 t2
WHERE  t2.tab1_code = t1.code
AND    t2.code like NVL(:p1,'%'))
ORDER BY t1.code;

CODE
----------
1
1
1
2
2
2
3
3
3

9 rows selected.

SELECT t1.code
FROM   tab1 t1
WHERE  EXISTS(SELECT rowid
FROM   tab2 t2
WHERE  t2.tab1_code = t1.code
AND    t2.code like COALESCE(:p1,'%'))
ORDER BY t1.code;

CODE
----------
1
2
3

3 rows selected.

From this you can see that then the bind variable is set to ‘%’ the query without the NVL works as expected, but the query using the NVL displays a row in the master table for each row found in the subquery. In comparison, the query using the COALESCE function works fine.

Now I realise that this is not a great query anyway, but you would still expect it to work!

Happy days in Tru64 land again 🙂

Once again I’m drawn to the inevitable conclusion that running Oracle products on anything but a tier-one platform is a bad idea. What’s more, judging by the recent arrival of Oracle 10g Release 2, there is now only a single tier-one platform. I don’t see a version for Solaris, HP-UX or Windows yet.

As for me, I’m still waiting for 10.1.0.4.0 to be released on Tru64. Release 2 is a long way off 🙂

Cheers

Tim…

TNS-12157 TNS:internal network communication error

It’s getting difficult and a little depressing trying to make a blog comment or forum post these days. It seems every time you do you risk offending someone.

Tag me stupid, baby! seemed more than a little relevant.

The comments associated with some high-profile blogs only serve to depress me more. It’s like the pedants and PC freaks have come out in force lately. I don’t know what the answer is and I’m sure, like everyone else, I am part of the problem, but I think everyone should take a step back from the keyboard and chill out!

I’m not sure how I’m going to approach my next posts as my enthusiasm has died a little due to all this.

Remember, this post is not about you, it’s not a criticism of you and if you take it that way you are merely proving my point.

Cheers

Tim…

The calm after the storm…

Things are just starting to return to normal… I hope 🙂

The disruption associated with the production hardware reconfiguration seems to have calmed down now. Of course, not all of the problems were associated directly with the hardware changes, but the time you spend on one problem distracts you from other jobs you should be doing, which in turn creates new issues.

We have finally moved all the database backups over to RMAN against HP Data Protector, rather than the disk-based RMAN backups we were doing before. The software seems to work fine, but the physical processes are taking some time to get used to. Rather than having a tape labeled “Monday night application X backup”, we now have a bank of tapes in a media pool that can hold portions of several backups. It’s not rocket science, but it can be a bit of a culture shock when you start changing processes that have been in place for years. It takes a while for people to get used to the idea that you don’t know which tapes must be removed and taken offsite until the software tells you.

Fun, fun, fun 🙂

Cheers

Tim…

SQLdetective Review

I was recently asked to review a product called SQLdetective, so here it is.

Q. What’s it for?
A. It’s for developers and DBAs and anyone else who does anything with an Oracle database.

Q. What features does it have?
A. It has everything you’ve come to expect from a general purpose DBA/Developer IDE. I’m not even going to attempt to list them because it would take forever. Suffice to say, if you’ve seen it in another product, it’s probably here.

Q. What’s it look like?
A. You can look at a bunch of screen shots here. Like most current IDEs it’s a bit busy. Not as plain as PL/SQL Developer, but not as busy as TOAD. The icons are “different”, but I’m not sure if that’s a good or bad thing.

Q. What’s it feel like?
A. I seems quite quick and responsive, but it does some odd things, like when you highlight a table in the navigator the default operation is to show you a page of data. I doubt this would be the first thing I would want to see.

Q. What’s it cost?
A. The basic price is US$99, but if you want all the add-on modules it’s going to cost a total of US$198. So the cost depends on what you need. It’s difficult to compare prices because you rarely have to pay list prices and each IDE has different optional modules. It’s more expensive than the free version of TOAD, and now JDeveloper is free you can do all your PL/SQL development and debugging using that if you’ve got the hardware to run it 🙂

Q. Tim, would you buy it?
A. If I was forced to use an IDE I would use TOAD or JDeveloper for free. I have both loaded on my PC and I never use them. If I was forced to buy a license for an IDE I would consider this product. My company recently bought licenses for PL/SQL Developer, but I still use a text editor and SQL*Plus 🙂

Conclusion:

If you really want to pay money for an IDE give this one a try. It’s got a lot of stuff in it. Alternatively, write good intrumented code and save yourself the cash.

I guess I could just copy and paste this review about almost any of the current IDEs, but at least I’ve kept my promise…

Cheers

Tim…

Firefox 1.0.6 and RAC update.

Looks like Firefox 1.0.6 is out, but the update checker doesn’t know it… Again.

Got through a night without a server crash on the production RAC. Feels like the old days again 🙂

Cheers

Tim…

PS. Posted two more chapters to the publisher today. That leaves me with one new one to write and one to tighten up then I’m finished. Must crack on and get it sorted before I have a nervous break down cause by a complete lack of sleep 🙂

2 become 0, occasionally…

It’s been an “interesting” couple of days.

Since we moved to the new configuration we’ve have had some intermittent server crashes, including one last night where both nodes crashed simultaneously. We’ve applied an OS patch that is meant to solve the problem, but we’re still in the “fingers crossed” stage at the moment. It’s meant some busy nights and annoyed users, but we’re moving forward.

You’ve gotta love it…. Not!

Cheers

Tim…

3 become 2, RAC nodes that is…

This weekend our production system was switched from a 3-node to a 2-node RAC.

We were originally using a 2-node RAC (2 CPUs per node) and we added a third node because the system was struggling to cope with the workload. The third node helped us out in some ways, but it caused a lot of trouble in others. Ever since it’s inclusion it became impossible to take one node out of the RAC without bringing the lot crashing down, so much for high availability. In addition, a substantial proportion (about 30%) of the wait states on the system were due to inter-node communication. Now I expected with more nodes there would be more inter-node communication, but it seems a bit excessive. Heaven only knows what would happen in a 4-node cluster…

After a lot of banter with Oracle and HP we’ve finally decided to try a 2-node RAC again, but this time with 3 CPUs per node. OK, it’s actually 4 CPUs per node, but one CPU in each node is permanently offlined, so as not to affect our current Oracle licensing.

All the hardware modifications are complete and all tests indicate that the system is up and running normally. Of course the true test will happen tomorrow morning when the users log in and start to break things 🙂

The best news of all is that the move back to a 2-node cluster means that we can once again shut down one node at a time if we need to do maintenence. This is a big plus.

If everything goes quiet over the next few days it means that I’m fire-fighting and the switchover didn’t go well.

I’d be curious to see how many people out there are using RAC on more than 2 nodes. I’ve only done this on Tru64 with 1og Release 1, but I can say without a shadow of a doubt that it doesn’t work properly. I’m curious if this is Tru64 specific problem or if there is a fundamental flaw in RAC for clusters with more than 2 nodes.

Cheers

Tim…