Ask with your own column names
Google Sheets will suggest a formula as you type, which works if you already suspect SUMIFS is the answer and just can’t remember the argument order. Most of the questions we see start further back than that, with a result in mind and no function at all: refunds per customer this quarter, or month-over-month growth on the Revenue column while skipping the months somebody left blank. Gemini in Sheets can help with some of those if your Workspace plan includes it.
dassi works in the browser you already use, so it can see the sheet you have open (tab names, headers, a sample of rows, what kind of data sits in each column). You describe the result and it writes the formula against your actual ranges and names.
A worked example
The Orders tab has the customer in column B, the amount in D, and a status column F reading Paid, Refund or Pending. On the Customers tab you want total refunds beside each name, so you ask: “In Customers, column E, total refunds per customer from the Orders tab.” dassi reads both tabs and proposes this for E2:
=SUMIFS(Orders!D:D, Orders!B:B, A2, Orders!F:F, "Refund")
It explains the pieces in a sentence (add up column D wherever the customer matches this row’s name and the status says Refund), tells you which cells it’s about to change, and waits if you’ve made writes to the sheet an approval step. Then it fills the column down and checks two customers by hand against the Orders tab. The headers and rows it reads along the way go to the AI provider you picked, on your own key or through dassi’s relay with included credits.
Long formulas are where we changed our minds. We used to like one clever formula per column. dassi tends to suggest a helper column once a formula starts reading like a paragraph, and having inherited a few of those sheets, we mostly agree with it now.
Where suggestions go wrong
Ranges that swallow the header row. Spreadsheets set to a locale that separates arguments with semicolons. An ARRAYFORMULA spilling into cells that already hold values, which throws #REF!, and dates stored as text, which look right and compare wrong. Testing on real rows catches some of this, and we don’t have a way to catch all of it, so read the first few results yourself before you trust the column.
The rest of the job
The formula is rarely the slow part. Getting the data into the sheet usually is, whether that means last week’s numbers from three dashboards or transactions from a bank site with no export button, and dassi can do that too, with the formula as one step in a saved workflow that runs on a schedule. Moving bank transactions into a budget sheet is the one we’ve written up in detail, and the Google Sheets page has others that end in a column of SUMIFS much like this one.