Constantin Lungu

Constantin Lungu

9 followers

Data Engineer with a passion for transforming complex data landscapes into insightful stories. Here on my blog, I share insights, challenges, and the ever-evolving dance of technology and business.

De-duplicating with ROW_NUMBER vs ARRAY_AGG

Dec 2, 20231 min read

What function do you use to explicitly de-duplicate in BigQuery?I normally use ROW_NUMBER(), but I've recently encountered a really interesting blog...

De-duplicating with ROW_NUMBER vs ARRAY_AGG

Using SELECT * with EXCEPT and REPLACE

Nov 30, 20231 min read

SELECT * is not a good practice in production, but I still use it for spot checks, when debugging, analyzing or validating data - especially when...

Using SELECT * with EXCEPT and REPLACE

Dunder / magic functions in Python

Nov 28, 20232 min read

One thing you might encounter in Python are the "dunder" (because of the double underscore before and after their name) or "magic" methods, because...

Dunder / magic functions in Python

Using STRUCTS for Audit Fields in BigQuery

Nov 25, 20233 min read

I use STRUCTS in #BigQuery quite a bit. One interesting use case for them is for audit purposes a separate column containing metadata about how the...

Using STRUCTS for Audit Fields in BigQuery

Comparing ranking functions in BigQuery

Nov 15, 20231 min read

One of the most common sightings in SQL code is using ranking functions. It's simple but we must surely get it right. I use ROW_NUMBER very often for...

Comparing ranking functions in BigQuery

Tidying up WINDOW functions in BigQuery with named windows

Nov 8, 20234 min read

So, if you ever find yourself working with multiple window functions in BigQuery, leverage the named windows specification for tidier, leaner...

Tidying up WINDOW functions in BigQuery with named windows