I was building a dashboard to compare some cloud vendor costs and hit a wall with the default column formulas. I needed to normalize data from three different sources into a single unit (cost per 1M API calls). The preset operations weren't cutting it.
Then I stumbled on the "Custom Formula" option in the column builder's advanced menu. This is a game-changer for anyone doing vendor comparisons. You can write expressions that reference other columns by name, just like in a spreadsheet.
A simple but powerful example I used:
`(Requests / 1000000) * CostPerMillion`
This let me take a column with raw request counts and a column with vendor-provided "cost per million" rates to generate a projected monthly cost. Before this, I was doing that calculation manually outside of Grok and importing the result.
Some immediate questions for others who've used this:
* How does this compare to similar features in Looker Studio or Power BI? Is the formula syntax more limited?
* Are there any pitfalls with data types? I noticed it seems to treat everything as floats.
* What's the most complex or useful formula you've built with this? I'm thinking about adding conditional logic for tiered pricing models next.
The ability to do this directly on the dataset before analysis or visualization saves a huge step. It feels like a hidden superpower for B2B software comparisons.