Grouped table
How this page is built
the gem renders it — this is all you write
Grouping is a render-time arrangement, like the layout. Add group_by: :publisher — the gem orders by the group key, splits the rows into collapsible groups (chevron in the header) and shows a per-group count. With 120 books, groups start collapsed beyond config.group_collapse_threshold (default 50), opening only the first; the open ones live in ?open=, so a half-expanded view is copy-pasteable.
app/views/groups/index.html.erb
<%= crud_collection @books, group_by: :publisher %> <%# belongs_to, enum or a column %>Read more: Grouping
| Cover | Title | Author names | Genre | Price | Publisher | Active | ||
|---|---|---|---|---|---|---|---|---|
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| Ace 2 | ||||||||
| Orbit 2 | ||||||||
 |
The Hidden Forest 1 | Frank Herbert, Ted Chiang, and Ann Leckie | Nonfiction | 28.24 € | Orbit | ✗ | ||
 |
The Luminous Ocean 108 | Ted Chiang | Nonfiction | 39.89 € | Orbit | ✗ | ||
| DAW 2 | ||||||||
| Baen 1 | ||||||||
| Del Rey 1 | ||||||||
| Vintage 1 | ||||||||
 |
The Quiet Dune 62 | Mary Shelley | Nonfiction | 24.14 € | Vintage | ✗ | ||