Change a column

A column is a field in the module's file, and Claude changes that file when you ask. This guide covers the four changes you will want most: add, rename, reorder and remove. None of them needs new code.

Where a column lives

Each datatable module has a module file, such as app/src/modules/people.json. Its fields list holds one entry per field:

{ "key": "lastContact", "label": "Last contact", "kind": "date", "tab": "Details" }
PartWhat it does
labelThe name you see on screen
keyThe name in the data file. Each row stores its value under this key
kindHow the value is typed in: line, text, lines, date, status, category, person, number, direction, period or owner
tabWhich tab of the row's sheet it shows on. Fields on the first tab are the table's columns; the rest show only in the sheet
hintAn optional line of help under the field

The order of the list is the order on screen. The first field is always name. Fields and views explains the kinds in full.

Add a column

"In People, add a column called Customer after Organisation. Kind: line. Leave it empty for every row."

Say the kind when you know it. If you do not, describe the value: "a date", "a long note", "one of the people in People". Claude picks the kind and tells you which.

To put a field in the sheet only, not in the table: "Put it on the Note tab, not in the table."

Rename a column

"In People, rename the column 'How you know them' to 'Context'."

A rename changes the label. Your data does not move. If you also want the key changed, say so: "Change the key too, and update every row." Claude must then rename the key in every row of the data file, or the values stop showing.

Reorder columns

"In Tasks, show Due before Person."

Claude moves the field in the list. Nothing else changes.

Remove a column

"In People, remove the Last contact column. Tell me how many rows have a value in it first."

Decide what happens to the values already stored:

ChoiceWhat happens
Remove the values tooClaude deletes the key from every row. Clean, but the values are gone unless you saved a checkpoint.
Keep the values in the fileThe column goes from the screen, but the next time you save a row on screen, its value for that field is dropped.
Move them"Add the last contact date to the end of Notes, then remove the column."

To hide a field from the table but keep it, move it to another tab instead of removing it.

Worked example: Sam's Customer column

Sam's People table listed contacts at Tallow & Co and Harbourline Logistics, but Organisation held both customers and colleagues at Brightlane. They wanted a column for the customer alone.

  1. "In People, add a column called Customer after Organisation, kind line."
  2. They checked People: a new empty column.
  3. "Fill Customer from Organisation for every row where Organisation is a customer. Show me the list first."
  4. They checked the preview, then said "Write it."

What to check

  • The column shows in the place you asked for, with the right name.
  • Open one row's sheet: the field is on the tab you expect.
  • Add a test value on screen and save it. Delete the test value after.
  • Existing values still show in the columns you did not touch.

Common problems

ProblemWhat to do
A column is empty after a renameThe key changed but the rows did not. Ask: "The Context column is empty since the rename. Fix the rows."
The new column is in the sheet, not the tableIt is on another tab. Ask Claude to move it to the first tab.
A date column will not take your dateType it as YYYY-MM-DD, such as 2026-10-14.
A status shows as Backlog after you typed something elseStatus takes only backlog, in-progress, blocked or done.
"Changed on disk — reload" when you saveClaude changed the file while your sheet was open. Copy what you typed and reload.