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The Variables pane

A new name. The same foundation. Fabric Desktop is now KratosForge. Some executable names and paths remain unchanged for compatibility. Legacy names explained ↗

View > Variables lists what the notebook's Python session holds on this PC: each variable's name, type, size and a short value. It's the same explorer Fabric and Databricks notebooks have. Reading it runs no cells and no queries; the only code of yours it can touch is a class's own repr, used for the short value, as any Python explorer does.

Filter and sort#

  • Type in Filter by name or type to narrow the list, for example DataFrame or sales.
  • Click Name, Type or Size to sort; click again to reverse. Size sorts by the memory a variable holds, biggest first; variables whose memory can't be told cheaply go last.
  • The line under the table counts the variables and adds up their memory.

Memory is an estimate: a Polars or Arrow frame's buffers, a NumPy array's bytes, or a built-in list, dict or set with its first 10,000 items, scaled up (an object inside counts its base size). A Spark frame, a Polars LazyFrame and your own classes have no figure, because measuring them would mean running their query or their code. Hover a size to see the estimate.

Open a variable#

The arrow next to a data frame, list, tuple, set or dict opens it in place:

Variable What you see
Polars, Arrow or Spark data frame Its columns and their types, read from the schema (a Spark frame's query isn't run)
List or tuple The first 100 items with their index, type and value
Set 100 of its items, sorted
Dict The first 100 keys with their type and value

Values whose name or content looks like a secret (password, token, key and the like, or a value read with getSecret) show as hidden, at the top level and inside an opened dict, and a hidden variable can't be opened. Opened variables close when the pane refreshes after a run, and reopen with the new values when you open them again.

Clicking a variable's row still adds a cell that displays it.

When the debugging Preview features are on, the same table is the pane's Now tab, beside watches and history.

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