@@ -43,6 +43,14 @@ When people upload a CSV to a collection, Metabase will:
- Create a table to store that data in the database and schema that the Admin selected to store uploads.
- Create a [model](../data-modeling/models.md) that wraps the uploaded table, and save that model to the collection the person uploaded the CSV data to.
## Primary key detection and auto-generation
When you upload data, Metabase will try to detect whether the uploaded CSV file includes a column with an incrementing ID. The check is pretty basic: it'll check for a column named `id` or `pk` that has integers for each row in the uploaded CSV. Each integer in this column should be unique, so if your CSV includes duplicate ID integers, the column won't work as [an entity key](../data-modeling/field-types.md#list-of-metabase-field-types).
If Metabase doesn't detect a primary key, it will create an ID column for you, including this ID column as the first (left-most) column of the uploaded CSV table.
If you don't want this autogenerated ID column, you can always remove the column from the model Metabase created. Visit the model, click on the info **i** icon, then **Model details**. From the model details page, click the **Edit definition** button. In the Data section of the query builder, click on the down arrow next to the table, deselect the added ID column, and save your changes.
### Add people to a group with unrestricted data access to the upload schema
In order to upload CSVs, a person must be in a group with Unrestricted access to the schema you've selected to store your uploaded data. Native query editing isn't required for uploading. See [groups](../people-and-groups/managing.md) and [data permissions](../permissions/data.md).
