> ## Documentation Index > Fetch the complete documentation index at: https://docsautomator.co/docs/llms.txt > Use this file to discover all available pages before exploring further. # Line Items > Add variable-length lists and tables to your documents DocsAutomator provides powerful capabilities for incorporating groups of variable-length data into documents. Line items represent lists of things where the quantity isn't predetermined—such as invoice line items, conference attendees, or recipe ingredients. **Line Items = Groups of data / lists of things** ## Syntax Line items are declared using the syntax `{{line_items_$num}}` at the beginning of a table row, with associated variables placed in subsequent cells. ``` {{line_items_1}}{{description}} {{quantity}} {{price}} ``` ## Data Source Mapping | Data Source | Mapping Method | | ------------- | --------------------------------- | | Airtable | Automation interface | | Notion | Relation property → related pages | | Google Sheets | Linked sheet selection | | SmartSuite | Linked field mapping | | Glide | Within Glide interface | | Noloco | Within Noloco interface | | Zapier | Zapier configuration | | API | Array of objects | ## Multiple Line Item Sets Multiple line item sets can be included by incrementing the number: ``` {{line_items_1}}{{description}} {{quantity}} {{price}} {{line_items_2}}{{name}} {{amount}} ``` Line item sets must be numbered in correct order (1, 2, 3, etc.). ## Features ### Adding Images in Line Items Image placeholders use the `{{image_name}}` prefix and can map single or multiple images: ``` {{line_items_1}}{{image_product_photo}} {{name}} {{price}} ``` ### Grouping Line items can be grouped by any variable except images. See [Line Items Grouping + Calculations](/features/line-items/line-items-grouping-+-calculations). ### Conditional Display Rows can be conditionally shown/hidden based on placeholder values through options/gear icons. See [Conditional Show/Hide](/features/advanced-placeholder-options/conditional-show-hide). ### Conditional Styling Text and rows support dynamic styling based on conditions: * Even/odd row alternating colors * Custom text formatting * Row background colors See [Conditional Styling](/features/advanced-placeholder-options/conditional-styling). ## Constraints * Variables must be unique per line item row * Line items must occupy entire rows, not partial rows * No limit on items passed (users report hundreds to thousands) * Each `{{line_items_N}}` number must be unique across the entire template — even if the tables are in mutually exclusive sections. Reusing the same number (e.g. `{{line_items_1}}` twice) causes a generation error. ## API Example When using the API, pass line items as an array of objects inside the `data` object: ```json theme={null} { "docId": "your-automation-id", "data": { "customer_name": "Acme Corp", "invoice_date": "2024-01-15", "line_items_1": [ { "description": "Widget A", "quantity": 2, "unit_price": 10.00, "total": 20.00 }, { "description": "Widget B", "quantity": 1, "unit_price": 25.00, "total": 25.00 } ] } } ``` ## Related Pages Create hierarchical data structures Group and calculate totals Automatic row numbering Complete template syntax