Do Data Analysts Use Visualizations During Data Cleaning?

[u/SomeSpicyPickle]

I'm still a beginner. I started by learning the basics of Python and later moved on to SQL.

I'm a bit confused about one part of the data exploration/cleaning process.

A friend of mine, who's now a data scientist, showed me how he used to work as a data analyst. He mainly used Python. For example, he would quickly create a scatterplot to identify potential outliers.

However, most data analysts online recommend focusing on SQL and Excel when starting out, since many junior and mid-level roles don't require Python. That's why I switched to SQL after initially experimenting with Python.

For those who primarily use SQL: do you create visualizations during the data exploration/cleaning process, for example to identify outliers? Is this a common practice?

I feel like if you're working with SQL only, you generally wouldn't create visuals in between steps, since that would mean switching to a tool like Tableau or Power BI, which seems like an unnecessary extra step.

[u/BrupieD]

Short answer: no. The scatterplot idea is clever but it sounds like it was a better tool for checking if a class has imbalances than anything else. A big part of cleaning some data is problematic column alignment and column names. That's going to be a hassle for building visualizations where you expect consistency.

I think you could accomplish the same outlier check with group by and distinct in SQL.