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!