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: :genre — 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: :genre %> <%# belongs_to, enum or a column %>Read more: Grouping
| Cover | Title | Author names | Genre | Price | Publisher | Active | ||
|---|---|---|---|---|---|---|---|---|
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| Nonfiction 9 | ||||||||
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The Hidden Forest 1 | Frank Herbert, Ted Chiang, and Ann Leckie | Nonfiction | 28.24 € | Orbit | ✗ | ||
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The Hidden Mirror 14 | Ursula Le Guin and Kim Robinson | Nonfiction | 22.58 € | Ace | ✗ | ||
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The Luminous City 45 | Ann Leckie, Kim Robinson, and Octavia Butler | Nonfiction | 19.30 € | Baen | ✗ | ||
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The Silent Station 60 | Becky Chambers, Octavia Butler, and Margaret Atwood | Nonfiction | 34.96 € | DAW | ✗ | ||
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The Broken Station 61 | Octavia Butler | Nonfiction | 18.89 € | DAW | ✗ | ||
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The Quiet Dune 62 | Mary Shelley | Nonfiction | 24.14 € | Vintage | ✗ | ||
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The Hidden Ocean 65 | Joe Abercrombie, Iain Banks, and Ann Leckie | Nonfiction | 43.18 € | Del Rey | ✗ | ||
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The Luminous Mirror 84 | Kim Robinson and Ann Leckie | Nonfiction | 19.40 € | Ace | ✗ | ||
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The Luminous Ocean 108 | Ted Chiang | Nonfiction | 39.89 € | Orbit | ✗ | ||