Merge pull request #193 from lolcabanon/docs/add-warning-column-id

Update `createColumns()` doc

docs/src/routes/docs/[...2]api/[...3]create-columns/+page.md

@@ -81,6 +81,12 @@ const columns = table.createColumns([
 
 #### `columnDef.id?: string`
 
+:::admonition type="warning"
+
+The `id` will be parsed with [`svelte-keyed`](https://github.com/bryanmylee/svelte-keyed), so make sure to format it without dot notation (`object.prop`) or array notation (`object[0]`).
+
+:::
+
 Defines the id of the data column. **Duplicate ids are not allowed** on a single table.
 
 _Defaults to the value of `accessor` if a string accessor is passed. If a function accessor is passed, defaults to the value of `header` instead_.