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Shape · Combine tables

Union

Stacks the rows of two or more tables one under another. Columns line up by name or by position.

Also known as: Append, concatenate, stack

How it works

Wire two or more tables (up to 26) into the inputs. Column matching is By name by default, which lines columns up by header and fills a column missing from one input with nulls, or By position, which stacks the first column on the first column and so on. Harmonize headers (by name only) fixes drifted headers before stacking: Auto-match case & spacing treats Qty, QTY and qty as one column, Add rename rule folds listed variants into a canonical name such as Quantity into Qty, and Unmapped columns either Keep (null-fill) or Fail the run when a column matches no rule. Rows are appended as they are; use a distinct step afterwards if you need duplicates removed.

Inputs and outputs

Inputs

  • input_0 — Table
  • input_1 — Table
  • input_2 — Table
  • input_3 — Table
  • input_4 — Table
  • input_5 — Table
  • input_6 — Table
  • input_7 — Table
  • input_8 — Table
  • input_9 — Table
  • input_10 — Table
  • input_11 — Table
  • input_12 — Table
  • input_13 — Table
  • input_14 — Table
  • input_15 — Table
  • input_16 — Table
  • input_17 — Table
  • input_18 — Table
  • input_19 — Table
  • input_20 — Table
  • input_21 — Table
  • input_22 — Table
  • input_23 — Table
  • input_24 — Table
  • input_25 — Table

Outputs

  • data — Table

Settings

The Attributes panel of Union, as in the app: the controls work, but nothing runs — there is no data behind it.

The same settings, as the Assistant writes them 
{
  byName: boolean
  harmonize?: { autoMatch: boolean, renameMap: { canonical: string, variants: string[] }[], onExtra: "keep"|"fail" }
}

byName: true = UNION ALL BY NAME (NULL-fill missing), false = positional. harmonize (#1168) renames drifted headers to a canonical schema first: autoMatch collapses case/space variants, renameMap folds synonyms, onExtra fails or keeps unmapped columns

Example

Twelve monthly exports have the same columns but the headers changed case halfway through the year. Wire all twelve in, keep By name, turn on Harmonize headers with Auto-match case & spacing, and add a rule mapping the variant Quantity to Qty.