n8n-docs/docs/data/data-mapping.md

Data mapping

Data mapping means referencing data from previous nodes. It doesn't include changing (transforming) data, just referencing it.

You can map data in the following ways:

• Using the expressions editor. Refer to expressions for more information.
• By dragging and dropping data from the INPUT table into parameters. This generates the expression for you.

How to drag and drop data

1. Run your workflow to load data.
2. Open the node where you need to map data.
3. Make sure the INPUT view is in Table layout.
4. Click and hold a table heading to map top level data, or a field in the table to map nested data.
5. Drag the item into the parameter field where you want to use the data.

Understand nested data

Given the following data:

[
  {
    "name": "First item",
    "nested": {
      "example-number-field": 1,
      "example-string-field": "apples"
    }
  },
  {
    "name": "Second item",
    "nested": {
      "example-number-field": 2,
      "example-string-field": "oranges"
    }
  }
]

n8n displays it in table form like this: