And now, let's update the edition to point at the next edition we hope to support:

```nu
open rustfmt.toml | update edition 2021
# => ─────────┬──────
# =>  edition │ 2021
# => ─────────┴──────
```

You can also use the [`upsert`](/commands/docs/upsert.md) command to insert or update depending on whether the column already exists.

### Moving Columns

You can use [`move`](/commands/docs/move.md) to move columns in the table. For example, if we wanted to move the "name" column from [`ls`](/commands/docs/ls.md) after the "size" column, we could do:

```nu
ls | move name --after size
# => ╭────┬──────┬─────────┬───────────────────┬──────────────╮
# => │ #  │ type │  size   │       name        │   modified   │
# => ├────┼──────┼─────────┼───────────────────┼──────────────┤
# => │  0 │ dir  │   256 B │ Applications      │ 3 days ago   │
# => │  1 │ dir  │   256 B │ Data              │ 2 weeks ago  │
# => │  2 │ dir  │   448 B │ Desktop           │ 2 hours ago  │
# => │  3 │ dir  │   192 B │ Disks             │ a week ago   │
# => │  4 │ dir  │   416 B │ Documents         │ 4 days ago   │
# => ...
```

### Renaming Columns

You can also [`rename`](/commands/docs/rename.md) columns in a table by passing it through the rename command. If we wanted to run [`ls`](/commands/docs/ls.md) and rename the columns, we can use this example:

```nu
ls | rename filename filetype filesize date
# => ╭────┬───────────────────┬──────────┬──────────┬──────────────╮
# => │ #  │     filename      │ filetype │ filesize │     date     │
# => ├────┼───────────────────┼──────────┼──────────┼──────────────┤
# => │  0 │ Applications      │ dir      │    256 B │ 3 days ago   │
# => │  1 │ Data              │ dir      │    256 B │ 2 weeks ago  │
# => │  2 │ Desktop           │ dir      │    448 B │ 2 hours ago  │
# => │  3 │ Disks             │ dir      │    192 B │ a week ago   │
# => │  4 │ Documents         │ dir      │    416 B │ 4 days ago   │
# => ...
```

### Rejecting/Deleting Columns

You can also [`reject`](/commands/docs/reject.md) columns in a table by passing it through the reject command. If we wanted to run [`ls`](/commands/docs/ls.md) and delete the columns, we can use this example:

```nu
ls -l / | reject readonly num_links inode created accessed modified
# => ╭────┬────────┬─────────┬─────────┬───────────┬──────┬───────┬────────╮
# => │  # │  name  │  type   │ target  │   mode    │ uid  │ group │  size  │
# => ├────┼────────┼─────────┼─────────┼───────────┼──────┼───────┼────────┤
# => │  0 │ /bin   │ symlink │ usr/bin │ rwxrwxrwx │ root │ root  │    7 B │
# => │  1 │ /boot  │ dir     │         │ rwxr-xr-x │ root │ root  │ 1.0 KB │
# => │  2 │ /dev   │ dir     │         │ rwxr-xr-x │ root │ root  │ 4.1 KB │
# => │  3 │ /etc   │ dir     │         │ rwxr-xr-x │ root │ root  │ 3.6 KB │
# => │  4 │ /home  │ dir     │         │ rwxr-xr-x │ root │ root  │   12 B │
# => │  5 │ /lib   │ symlink │ usr/lib │ rwxrwxrwx │ root │ root  │    7 B │
# => │  6 │ /lib64 │ symlink │ usr/lib │ rwxrwxrwx │ root │ root  │    7 B │
# => │  7 │ /mnt   │ dir     │         │ rwxr-xr-x │ root │ root  │    0 B │
# => ...
```

### The # Index Column

You've noticed that every table, by default, starts with a column with the heading `#`. This column can operate in one of two modes:

1. Internal #

   - The default mode
   - Nushell provides a 0-based, consecutive index
   - Always corresponds to the cell-path row-number, where `select 0` will return the first item in the list, and `select <n-1>` returns the nth item
   - Is a display of an internal representation only. In other words, it is not accessible by column name. For example, `get index` will not work, nor `get #`

1. "Index"-Renamed #

   - When a column named "index" is created, either directly or as a side-effect of another command, then this `index` column takes the place of the `#` column in the table display. In the table output, the column header is still `#`, but the _name_ of the column is now `index`.

     Example: