The Drunkard’s Walk, a book worth reading twice, or more. A Data Analyst perspective

As you know, if you follow my LinkedIn profile (which, if you doesn’t, you should) I was reading Leonard Mlodinow’s “The Drunkard’s Walk”, a really great book if you want to get a grasp on how chance, or how randomness, affects our lives, and, what is better, how we fail to perceive what is chance,Continuar lendo “The Drunkard’s Walk, a book worth reading twice, or more. A Data Analyst perspective”

4 Insights you can gather from Michael Lewis’ Moneyball as a Data Analyst

If you follow me on LinkedIn you already know that I’m, or actually was, reading Moneyball. Just finished the book today, and so I thought it would be fun to share what I got from this book using my perspective, in other words, a data analyst’s perspective. It’s no surprise that this book is, orContinuar lendo “4 Insights you can gather from Michael Lewis’ Moneyball as a Data Analyst”

SQL Soccer Questions

Recently I came across a SQL interview question, the “SQL Soccer Matches” question, have you seen this already? This is the kind of question you can find in an interview exam. Anyway, in order to answer that I developed many approaches to solve it: using union, using many ctes and union, using case sum, andContinuar lendo SQL Soccer Questions

SQL Interview Questions

I’m going big on SQL these days. I always loved SQL, but this couple last days I’m going hard on learning and mastering it. There’s still lot to do, many courses to take, many books to read, and many exercises to do. Talking about exercises, this guys Nick Singh just lunched a site with questions,Continuar lendo “SQL Interview Questions”

[Solved, Spoilers] SQL Murder Mystery – Can you find out whodunnit?

Here: https://mystery.knightlab.com/ So, couple of friends of mine send me this challenge, and it’s really fun. Go there and try it! The plot is: someone killed someone else, and you, as the detective, need to find out who did it. Your weapons are SQL, table and relationships. Off you go! My solution to this OnContinuar lendo “[Solved, Spoilers] SQL Murder Mystery – Can you find out whodunnit?”

Informatica Powercenter – XML Transformation (XML Source Qualifier, XML Parser, XML Generator)

I highly recommend reading the first three links on References, at the end of this post. About XML What says the official documentation: “Each group in an XML source definition is analogous to a relational table, and the Designer treats each group within the XML Source Qualifier transformation as a separate source of data.” TheContinuar lendo “Informatica Powercenter – XML Transformation (XML Source Qualifier, XML Parser, XML Generator)”

Informatica Powercenter – Stored Procedure Transformation

Let’s start checking out what the official documentation has to say: “A Stored Procedure transformation is an important tool for populating and maintaining databases. Database administrators create stored procedures to automate tasks that are too complicated for standard SQL statements. The Stored Procedure transformation is a passive transformation. You can configure a connected or unconnectedContinuar lendo “Informatica Powercenter – Stored Procedure Transformation”

Informatica Powercenter – SQL Overrides

I did not really find any super good resource on this topic, but the overall idea of SQL override is to override a transformation default behavior by writing a SQL query instead. Of course, SQL overrides works only on relational data. There is no SQL Overrides for flat file. For instance, take a source qualifierContinuar lendo “Informatica Powercenter – SQL Overrides”

Informatica Powercenter – User Defined Functions

User Defined Function (UDF’s) is a way Powercenter gives us to create our own personal, reusable, functions. We can use our UDF’s in Expression Transformations in order to reuse expression logic. For instance, if you want to RTRIM() LTRIM() and UPPER() several ports, so, instead of writing all these 3 functions all the time youContinuar lendo “Informatica Powercenter – User Defined Functions”

Informatica Powercenter – Mapplets

Here what official documentation says about Mapplets: A mapplet is a reusable object that you create in the Mapplet Designer. It contains a set of transformations and lets you reuse the transformation logic in multiple mappings. When you use a mapplet in a mapping, you use an instance of the mapplet. Any change made toContinuar lendo “Informatica Powercenter – Mapplets”

Informatica Powercenter – Update Strategy Transformation SCD1 SCD2

Something worth keeping in mind: in order to Update Strategy to work properly you need to make sure that your target table has a primary key. Here’s what the official documentation says about Update Strategy Information: “The Update Strategy transformation is an active transformation. When you design a data warehouse, you need to decide whatContinuar lendo “Informatica Powercenter – Update Strategy Transformation SCD1 SCD2”

Informatica Powercenter – Union Transformation

If you are familiar to SQL you already know what UNION does. In fact, you might be wondering, is Powercenter Union the same as SQL union or SQL union all? It is UNION ALL. Here’s the official documentation on Powercenter Union transformation: The Union transformation is a multiple input group transformation that you use toContinuar lendo “Informatica Powercenter – Union Transformation”