Grouped table

Group by publisher Group by genre
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
— 19
Tor Books 11
Ace 16
Orbit 9
Gollancz 11
DAW 19
Baen 8
The Dispossessed Station 12 Martha Wells and Ann Leckie Nonfiction 16.58 € Baen ✓
The Burning Door 36 Kim Robinson Nonfiction 31.42 € Baen ✓
The Silent Tower 39 Ann Leckie, Mary Shelley, and Ursula Le Guin Nonfiction 25.60 € Baen ✓
The Luminous City 45 Ann Leckie, Kim Robinson, and Octavia Butler Nonfiction 19.30 € Baen ✗
The Distant Tower 63 Iain Banks, Liu Cixin, and Joe Abercrombie Scifi 18.55 € Baen ✓
The Luminous Forest 68 Liu Cixin, Ann Leckie, and Ursula Le Guin Nonfiction 40.60 € Baen ✓
The Endless Ocean 105 Liu Cixin and Kim Robinson Scifi 34.90 € Baen ✓
The Burning Station 110 Mary Shelley Nonfiction 24.38 € Baen ✓
Del Rey 12
Vintage 15