> ## Documentation Index
> Fetch the complete documentation index at: https://docs.firstresonance.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Part Inventory Imports

> Create or update part inventory records from a CSV file.

## Overview

The Part Inventory importer creates new inventory or updates existing inventory from a single CSV. The distinction is row-by-row:

* Rows **without** an `id` value **create** new inventory. `part_number` is required.
* Rows **with** an `id` value **update** the matching inventory record. `part_number` and `revision` are ignored on update.

Creates run through the same path used by the UI, so aBOM creation, serial autogeneration, and tracking-type validation all apply. Updates run through the matching update path, so cascade behavior (location propagation, quantity validation, etc.) is preserved.

## Columns

| Column                | Required         | Description                                                                                                                                                                             |
| --------------------- | ---------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `id`                  | No               | Inventory ID. Provide to update an existing record; omit (or leave blank for the row) to create new inventory. **Lookup column** — an empty cell is treated as "not provided," not `0`. |
| `part_number`         | Yes (for create) | Part number for new inventory. Ignored on update.                                                                                                                                       |
| `revision`            | No               | Part revision. Combined with `part_number` to look up the part; if omitted, the latest revision is used.                                                                                |
| `serial_number`       | No               | Serial number.                                                                                                                                                                          |
| `lot_number`          | No               | Lot number.                                                                                                                                                                             |
| `quantity`            | No               | Quantity. Must be non-negative. Empty cells become `0`.                                                                                                                                 |
| `quantity_scrapped`   | No               | Scrapped quantity. Must be non-negative. Empty cells become `0`.                                                                                                                        |
| `location`            | No               | Location name. Must match an existing location in ION.                                                                                                                                  |
| `supplier`            | No               | Supplier name. Must match an existing supplier in ION.                                                                                                                                  |
| `unit_of_measure`     | No               | Unit of measure name. Must match an existing unit in ION.                                                                                                                               |
| `intent_option`       | No               | Intent option value. Must match a configured intent option.                                                                                                                             |
| `autogenerate_serial` | No               | When `true` on a create row, ION generates a serial number. Cannot be set on update rows. Boolean field (see [accepted values](/administration/ion-importers#accepted-boolean-values)). |
| `autogenerate_lot`    | No               | When `true` on a create row, ION generates a lot number. Cannot be set on update rows. Boolean field (see [accepted values](/administration/ion-importers#accepted-boolean-values)).    |

<Info>
  Name-valued fields (`location`, `supplier`, `unit_of_measure`, `intent_option`) are resolved case-insensitively against existing records. An unrecognized name produces a row-level error.
</Info>

<Warning>
  `autogenerate_serial` and `autogenerate_lot` only apply on create rows. Setting either to `true` on a row that includes an `id` is rejected. Remove the `id` or the flag to fix the row.
</Warning>

## Custom attributes

Any column not listed above is treated as a custom attribute on the part inventory. Custom attribute columns must match a configured attribute key for your organization; unknown columns cause a validation error.

## Related pages

For general import behavior, empty cell handling, and error reporting, see [Importers](/administration/ion-importers).