Hi, I'm Rodrigo Ferreira
Data analysis & data engineering — notes, tutorials, and things I build.
I'm a Power BI and Microsoft Fabric consultant with over ten years of experience across Brazil, China and Portugal. This is where I write up what I work out along the way — and keep the references I got tired of looking up twice.
Latest writing
All posts →Example post — everything the site can do
A working demo of every feature available when writing a post. Delete this file once you have posts of your own.
#example #tutorial
Why your Power BI model is slow (and what a star schema fixes)
Most slow reports are not a DAX problem. They are a modelling problem, and the fix is older than Power BI itself.
#power-bi #modelling #dax
Window functions, explained without the jargon
Running totals, rankings and "compare each row to its group" — all without a self join.
#sql #tutorial
VLOOKUP, INDEX/MATCH, XLOOKUP — which to actually use
Three ways to do the same job, twenty years apart. Only one is worth learning today.
#excel #tutorial
dbt for people who already know SQL
If you can write a SELECT, you are most of the way there. The rest is file layout and two macros.
#dbt #sql #data-engineering
Projects
All projects →Monitoring every Fabric and Power BI item without being the admin
A PySpark-to-Power-BI pipeline giving a single, filterable view of every item I can see (owner, last refresh, status) with a one-click email to whoever owns something that's failing.
power-bi · fabric · data-engineering · power-automate
Example project
A demo entry showing how a project page is written. Delete it once you have real projects.
example · power-bi
Regional sales dashboard
A Power BI report replacing a 40-tab spreadsheet that took two days a month to assemble by hand.
power-bi · dax · modelling
Pipeline monitoring without a monitoring product
Freshness and row-count checks written as dbt tests, surfaced on a single page. No new vendor.
dbt · data-engineering · sql
Cheat Sheets
All cheat sheets →Pandas ↔ SQL
The same operation in both, side by side. For when you know one and are reaching for the other.
python · sql · pandas
DAX quick reference
The patterns that come up constantly — time intelligence, filter context, and the difference between the two X functions.
power-bi · dax
Git commands worth memorising
The dozen commands that cover almost everything, plus how to undo the three mistakes everyone makes.
git · tooling
Regex for data cleaning
The small subset of regular expressions that covers most messy-column problems.
regex · python · tooling