Tag Archives: sql

SQLskills Community Mentoring and me

As some of you might be aware Paul Randal (blog | twitter) has just announced the launch of a new SQL Skills Community Mentoring program for a few individuals that took part in the SQL Skills Immersion Events. I’m deeply honored to be one of the select few that get access to invaluable advice from what I consider the best team in the SQL Server world.LukeAndPaul

Allow me to go back to a year ago (and boy what a great year 2011 was), when I could only dream of getting trained by Paul Randal and Kimberly Tripp, but my perseverance paid off and after multiple requests,  me and my buddy Vince managed to convince the company to send us to the first week of Immersion training in May this year especially since it was in the western suburbs of Chicago. Very soon I realized that this is by far the best training I have ever received, period. The amount of content was overwhelming (as Brad put it “it’s like drinking from a proverbial fire hose”) but the presentation style was extremely engaging and well prepared. Paul and Kimberly don’t just tell you “this is what you should/shouldn’t do” they go beyond that and explain why and how  and then they demo the whole concept. Just like a good teacher they can take a difficult topic  and present it in a way that makes it easy for you to follow and absorb  a lot of  information.
On the fourth day of the IE 1 class I volunteered to present a slide deck. I was extremely embarrassed as I felt like I was not in the same league as the rest of the folks present, but everything went so well that it made me reconsider my thoughts. As a matter of fact it made me submit  a couple sessions for SQL Saturday #82 in Indianapolis and this was the beginning of my public speaking adventure. A few days ago I actually presented the same slide deck from IE1 at SQL Saturday #96 in Washington, DC and the feedback was excellent.

Last month I continued my learning odyssey with the second week of training (IE2). Right away  the fact that we attended IE1 made a huge difference and it helped us understand a lot better the subjects presented to us. This time it wasn’t just Paul and Kimberly but Jonathan and Joe  have joined them adding their technical skills and expertise to the table.   I learned so many new things that I have already used in my environment.

To conclude, these classes have helped me to understand significantly better how SQL Server works. Things like PLE, forwarding records, heap fragmentation, index tuning, page structure, SAN performance, waits and stats, extended events, NUMA architectures, MCM program are only a few of the subjects that were explained in great detail.

Now on the last binary day of  the century all this becomes even better by having the unique chance to have someone like  Joe Sack as Mentor and working with him to advance my career. It’s been an incredible year for me and I look forward to work with my Mentor Joe Sack and  see what the next 6 months will bring !

Once more, thank you SQLskills. It is an honor to be in such good company.

 

 

Using CONVERT with COLLATE to strip accents from Unicode strings

Today Mladen Prajdic  posted a on Twitter a SQL statement that captured my attention: (http://twitter.com/MladenPrajdic/status/9878219727)

SELECT
 CONVERT(varchar(50), N'æøåáäĺćçčéđńőöřůýţžš')
 COLLATE Cyrillic_General_CI_AI
returns aoaaalcccednooruytzs

If you notice the conversion to Cyrillic_General_CI_AI collation his shows an interesting mechanism for code page translation that we could not explain:

Why does Cyrillic_General_CI_AI or   Greek_CI_AI collation successfully convert accents to their base ascii chars?

 I found an answer to this on this KB page: http://support.microsoft.com/kb/153449

What Happens when a Character on One Code Page is Unavailable on Another

 If a conversion occurs and a character on one code page is unavailable on another, the character gets converted to its closest equivalent character on the other code page. For example, ASCII 224 (“alpha”) on code page 437 is converted to 97(“a”) on the ANSI code page. When you convert it back to code page 437, you receive 97(“a”). This is a problem, because you have now lost the original 224(“alpha”). This can potentially cause incorrect data to be saved on your server, as happens in the following two examples:

Example 1:

You have an OEM server in which you are inserting data from an ANSI client, and your AutoAnsiToOem option is enabled. If the character that you are inserting is valid in both code pages, the correct data will be saved. However, if the character is valid in ANSI but not in OEM, the correct data will not be saved.

Example 2:

You insert data into an ANSI server from an OEM client, and the AutoAnsiToOem option is enabled. If the character that you are inserting is valid in both code pages, the correct data will be saved. However, if the character is valid in OEM and not in ANSI, then correct data will not be saved.

 Nevertheless I this is very useful to exotic strip accents from strings (i.e before an export).

 

What three events brought you here?

Recently Paul Randal (aka Mr. Tripp)  started a web version of the tag game in the SQL Server blogging community  on what were the three most important events that shaped your career and got you to this point in your life. It is a very difficult question because unlike data, life events do not accept a SELECT TOP 3 … ORDER BY [ImportanceRating]. The sorting function is a subjective one for humans in the case of life changing events and it depends on the impact that one event had on the individual. It is a lot harder than most would think and I spent the weekend thinking about this and trying to review what were the most important events that shaped my life and career. Here’s what I came up with:

1) My FamilySinclair ZX Spectrum+

As I grew up in a communist Romania I was one of the fortunate kids that had access to technology thanks to my parents, both University Computer Science professors. My father is still teaches Databases from the 101 course to Oracle PL\SQL  and also Assembly Language. My mom is now retired but she used to teach the Fundamentals of Computer Programming  to students in the freshman year. As a kid I got to see all the  different generations of technology from things like ferrite memory to BASIC programming on Romanian replica of Sinclair ZX Spectrum+ Z80 home computer. I have thank my parents for explaining to me how things work and as a very inquisitive boy I absorbed all that information without realizing that one day this will help me understand the systems as a whole and see the big picture where others only see the frontend. The first database I worked on was dBase III the precursor of FoxPro (anybody who used it understands why some people call database tables “files”). The interesting side to this is that while I was hooked on computers, my sister decided to go to Law School to finally land in the wireless communications industry.

2) Discovering relational algebra

During third year in the Politehnica University I found an opportunity to apply for a EU scholarship in the frame of Erasmus Programme. I remember that one of the requirements was to be fluent in French and because of that there were only 3 or 4 students that applied and I was selected. I chose the “DB and Artificial Intelligence”  major at “Universite de Paris 6 – Pierre & Marie Curie“  and one of the courses was  “Relational Databases”. We started from the basics of the relational algebra operations and representing query plans as a tree  that can be transformed, all of which which I was fascinated by. I kept my interest in this when I returned home after my year in Paris, I got my Software Engineering MS in “Database Systems Optimizations”.

3)Real world challenge

After my graduation I  decided to continue the family tradition and started teaching Labs on “Programming Languages” and “Relational Database Design” at the  Politehnica University. A few years later I  decided to get a job as Oracle DBA. The first day on the job they gave me a desktop and some form of an install manual for Oracle and their product  and asked me to read it and ask around if I had questions. Two days later, to everybody’s surprise I had their product installed and running on Oracle 9i while it was designed for 8i. This was one of the first moments when I realized that I like challenges and that I can live up to the expectations.
A few years later came a moment when I realized just how lucky I am. It was the moment when I found out that I was one of the one selected for the Diversity Visa program to get a Green Card  and move the US.  

From that point forward I did not find it hard to get a job (I got my first job in US in three days) but I learned that the most important thing is to find the right job and the right employer that would challenge me just like Brent Ozar was writing in his post on the same subject:

I want to be a successful employee in my employer’s eyes, but when I take a job, one of the questions is, “One year after someone’s taken this position, what does success look like?  What is the best employee doing?  How are you rewarding them for what they’ve done?” 
In IT, this question takes people by surprise, but the answers reveal a lot.

Until this day I can proudly say that I have exceeded all my employers’ expectations but I cannot say the same about all the jobs I held.

I’m going to tag Ted Krueger, Jorge Segarra, Mladen Prajdic and Jonathan Kehayias to see how they are answering this question. The list does not have to end here. If you would like answer this question please link back to this post or the original post by Paul.

SQL Server 2008 Failover Clustering with High Availability

I’m heading home from the August session of Chicago PASS and SSUG meeting.
First off, this was the biggest meeting in Chicago. Over 80 people signed up and for a very good reason.
After a very interesting Microsoft SQL Server 2008 Administration with Windows PowerShell presentation by The MAK and Yan Pan,  Allan Hirt managed to cram the essentials of the new MS Failover Cluster Manager and he made it in less than an hour!
One very interesting and long awaited feature is Live Migration. Basically for the first time you can failover a MS Cluster without dropping any transaction. This is only happening for planned failovers of course but this is a phenomenal achievement for the MS team. Until now any time you would failover a cluster, the operation was the equivalent of stopping the SQLServer service an restarting it on a different machine. Obviously any pending transactions were dropped. With Live Migration the when a planned failover is initiated data from memory is copied over to the new active node and all transactions are seamlessly ported over as well. There might be some performance decrease but no transactions are dropped achieving true High Availability.
And last but not least all this is free with Windows Server 2008 Enterprise or Datacenter
For more information read this blog from Microsoft.
http://blogs.technet.com/virtualization/archive/2009/05/06/microsoft-hyper-v-server-2008-r2-release-candidate-free-live-migration-ha-anyone.aspx

Thanks Allan!