Chaos

.NET Access Automation

2011-10-18T16:06:00.000+08:00

This error makes me sick !!

Retrieving the COM class factory for component with CLSID {73A4C9C1-D68D-11D0-98BF-00A0C90DC8D9} failed due to the following error: 80080005.

I searched on Google for the solution but it seems no one knows the answer.

Run-time Error '2191' When Setting a Subreport's Control Source

2011-07-26T11:35:00.002+08:00

If you got this error when setting a sub-report's control source trough code,

Try to use this code in the sub-report's Open event :

Static Initialized As Boolean
If Not Initialized Then
   Me.RecordSource = "" ' Add your record source here
   Initialized = True
End If

High-Availability Database Solutions

2010-01-03T18:30:00.003+08:00

Last month I delivered a training about Designing High-Availability Database Solutions Using Microsoft® SQL Server™ 2005 for three days. It made me a lil bit stressed coz the subject was new for me and my student was a Senior DBA with plus-minus 12 years of experience. Can you imagine? :D

Well, let's start with an overview.

The availability of a database refers to the overall reliability of the system. A database that’s 100% available is one that never goes down. For some databases, being down for an hour is not a problem; for others, 30 seconds of downtime is catastrophe. It’s all depends on organization’s requirements.

Microsoft® SQL Server™ 2005 has several solutions for making database systems highly available. There are failover clustering, log shipping, mirroring, and replication to protect users from hardware, software, and process failures.

Clustering

Generally, the goal of a cluster is to enable the sharing of a computing load over several systems without users knowing that there is more than one system involved. If any hardware or software components in the system fail, the users may see degraded performance but will not lose availability to the database solution.

In failover clustering, what you’re doing is making copies of your hardware. For example, you’re gonna have identical hardware on identical servers. You’ll have the same username of logins, you’ll have all the same applications, you’ll have SQL Server instance installed on the servers, so you have a copy of one or more nodes. However, the actual storage is not copied. You only have one copy of your database. So, if you’re using clustering, you need to make sure that you have some kind of high-availability solutions for the data itself.

Clustering is based on Microsoft Clustering Service (MSCS) so it requires hardware that is listed on the Hardware Compatibility List (HCL). This solution is considered as the most expensive one and the most robust one.

Mirroring

Another solution available to us is database mirroring. Mirroring is less expensive than clustering and easier to set up. With mirroring you can use more flexible hardware, any hardware that is supported by Windows 2003; whereas in clustering, your choices are more limited because clustering requires hardware that’s listed on HCL.

Database mirroring does protect against disk failure because the mirror is actually a copy of our database; whereas in clustering, two or more nodes share a disk so that if the disk get corrupted then you’re in trouble!

Log shipping

The basic concept behind log shipping is to take advantage of the backup and restore operations in SQL Server. Log shipping allows us to automatically send transaction log backups from the primary database to a secondary database on potentially multiple servers. These transaction log backups are restored to the secondary database; this keeps it synchronized with the primary database.

Replication

Replication allows us to make data redundancy across servers. It’s pretty easy using replication if you got a database that has several tables or views, functions or procedures, and you wanna have those copied over other databases. If for any reason your original database gets corrupted, at least you have copies of that data on some other databases.

Each solution for a high-availability has unique advantages and drawbacks. There is no one solution that’s considered as the best solution because it will depend on the situation of organization. So, a good DBA must be able to determine the most appropriate solution for his/her business needs and deploy the solution in a manner that takes maximum advantage of its benefits while minimizing its drawbacks. In additional, remember that the technology alone cannot provide a high-availability solution. You must also have the right people and processes in place to support the technology.

Good luck !! :)

Farewell

2009-01-16T13:14:00.009+08:00

Time to say goodbye for all my friends in Bali...

Today is my last day in Mitrais. For me, it was not an easy decision to make, coz I really love both my job and this company. But, yeah, my manager was right. I have come to a point where I need to decide what is the most important thing in my life at this point in time. No one can stand between me and my dream. So please, say "good luck" for me :)

Thank you all... Luv you, and I'll miss you... :-*

Image of the Day: Persona

2009-01-04T14:45:00.024+08:00

Found this image in my PC when reorganising my files. It was made by nocturne for about 7 months ago. Cool, rite?

We wear masks when interacting with others. What we show to them is just a façade. We need different mask to face different people; even they’re our family, our friends, or our partners at work.

Do you still realise who you really are? Your truly face without any mask?

Quote of the Day

2009-01-04T09:00:00.001+08:00

“We know what we want to do, but afraid of hurting those around us by abandoning everything in order to pursue our dream. We do not realize that love is just a further impetus, not something that prevents us going forward. We do not realize that those who genuinely wish us well want us to be happy and are prepared to accompany us on that journey”

- Paulo Coelho

Night Flight

2008-12-05T09:20:00.007+08:00

I'm leaving Bali today. I don't know... what will happen tonight, tomorrow, or next year. I fear.. because my life will definitely change after this night. Whatever this journey involves, it will make a big difference in my life.

Hello World

2008-11-09T14:16:00.001+08:00

This is my first post on this blog. I made this blog, but still don't know what I'm going to write here. I wish I could write something that can be useful for others or make them feel something.

But now, I'm just feeling nothing.