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 17 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
— 3
The Dispossessed City 4 Kim Robinson, Margaret Atwood, and Adrian Tchaikovsky Fiction 19.95 € — ✓
The Burning Winter 6 Octavia Butler Scifi 21.78 € — ✓
The Endless Station 11 Joe Abercrombie Scifi 10.86 € — ✓
Tor Books 1
The Endless Dune 17 Joe Abercrombie, Mary Shelley, and Stanisław Lem Fiction 18.69 € Tor Books ✓
Ace 2
Orbit 1
The Hidden Forest 1 Frank Herbert, Ted Chiang, and Ann Leckie Nonfiction 28.24 € Orbit ✗
Gollancz 1
The Broken Engine 9 Ted Chiang, Ann Leckie, and Frank Herbert Fiction 32.99 € Gollancz ✗
DAW 3
The Ancient Winter 3 Joe Abercrombie Fiction 24.81 € DAW ✗
The Distant City 10 Stanisław Lem, Ted Chiang, and Liu Cixin Scifi 26.91 € DAW ✓
The Endless Station 13 Ann Leckie, Martha Wells, and Ursula Le Guin Fiction 27.05 € DAW ✗
Baen 1
Del Rey 3
The Quiet Mirror 5 Kim Robinson, Liu Cixin, and Becky Chambers Nonfiction 32.73 € Del Rey ✓
The Endless Forest 15 Octavia Butler, Ann Leckie, and Liu Cixin Scifi 11.84 € Del Rey ✓
The Ancient Signal 16 Joe Abercrombie Scifi 35.51 € Del Rey ✗
Vintage 2