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Five Reasons why a QlikView Developer Should know SQL

Luminary
Luminary

Five Reasons why a QlikView Developer Should know SQL

Without a doubt we all agree that QlikView is intuitive to use. Not just as a business user, even developing a QlikView application is an intuitive process. However, understanding SQL programming is important because most of the medium/large QlikView applications fetch data from transactional databases or a data warehouse. As a QlikView developer it’s important that you should be able to read & write SQL. Here are five reasons why QlikView developers should know SQL.

5. Be a superhero: Most companies store their data in database(s) and you need to understand SQL querying/programming to extract this data. Instead of relying on a database developer or a DBA to write the SQL query or a stored procedure you can write it yourself. I’m sure your manager would be happy that he doesn’t need to chase the database developers to extract the data. Ability to read & write SQL queries and a stored procedure is a good skill for any QlikView developer. Not just in your current role, but having an additional feather in your cap is always good on your CV. You never know when you may need these additional skills; you may need the skills in your next role.

4. Increased communication with DBA(s): With SQL knowledge, you can speak the DBA language and in my experience they love it. Being a DBA myself in the past, I always enjoyed conversations with those developers who understood the database world. With good SQL knowledge, you will be more likely to ask the right questions and avoid communication barriers.

3. Don’t kill the puppy: Some of you might have transitioned as a QlikView developer from working on Excel, VB & CRM systems etc. You are good with traditional procedural programming language but sometimes it’s more efficient to solve the problems using SET based approach. Using a cursor instead of a SET bases approach is a real curse for system performance. As a traditional developer, our natural way to solve any problem is by using the row-by-row approach and this would kill the performance. So, every time you use the cursor instead of a SET based approach; you are killing a puppy!

2. Reduce the reload time: Writing SQL queries might seem simple because the language is close to plain English. But writing optimised queries or stored procedures are key factors for both database & QlikView. You can save on reload time if you understand the slow performing queries or SQL tables without any indexes. Writing optimized SQL queries or stored procedures will help you reduce the overall application reload time.

1. Can’t run away from Joins: SET theory, predicate logic and relational algebra are the foundation pillars of SQL. QlikView offers various flavours of Joins and it’s important to understand the joins for “ET” bit of “ETL”. QlikView Joins have different syntax compared to ANSI SQL Joins but the underlying concept is largely the same. For beginners, Joins might be overwhelming but they are simple once you learn them. I have produced some video tutorials on QlikView Joins and which are a good starting point.

With SQL knowledge, you will start loving columns instead of rows!


Cheers,

DV

www.QlikShare.com

Comments
Not applicable

I agree with number 3. Too often I have come across application developers who are used to trolling through rows using cursors and wondering why their procedures are inefficient; naturally the hardware is to blame and not the method.

Luminary
Luminary

Great post DV, of course I liked point number three the most !!!!

saradhi_it
Contributor II

Hi Deepak..

   Nice post .....

0 Likes
Not applicable

Hi DV,

where is the video tutorials on QlikView Joins.What is the url address. pl provide. tks

NA

0 Likes
MVP & Luminary
MVP & Luminary

Nice and descriptive post Deepak.  Good Job.

Regards,

Jagan.

Luminary
Luminary

NA - Here you go...

http://qlikshare.com/?s=Joins

Good luck!

0 Likes
vikasmahajan
Esteemed Contributor

Hii

Deepak Nice Post Thanks for sharing  about point Reduce the reload time 

do you have any guide lines for improving sql queries how to optimize sql query ?

Vikas

0 Likes
travelindata
New Contributor II

Great post ! With the passage of time, I'm taking more attention to this question.

0 Likes
Luminary
Luminary

DV - Just a thought, you mentioned your videos in the post. I see you have your link to QlikShare at the bottom although maybe that's not too obvious thats where they are.....

Luminary
Luminary

Thanks Richard. I've added the link above in comments. Probably, I should add the link to original post as well.

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