Nested Table Grouping (Multi-level Grouping)

[gflaminio3]

Hi everyone!
I'd like to propose adding nested (multi-level) grouping support for Filament Tables.

Right now, tables can only be grouped by a single column, or users can switch between different grouping options — but we can’t have hierarchical groupings like Author → Status → Month in the same view.

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Why

This would make Filament Tables much more powerful for analytics and reporting use cases.
Typical examples:

• Sales grouped by region → category → month
• Posts grouped by author → status
• Transactions grouped by account → period

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Proposed API

Something like this could work nicely:

->groups([
    Group::make('author.name')
        ->thenBy('status')
        ->thenByDate('created_at', precision: 'month')
        ->collapsible(),
])

Or maybe introduce a NestedGroup helper:

->groups([
    NestedGroup::make('author.name')
        ->thenBy('status')
        ->thenBy(fn () => Group::make('created_at')->date()),
])

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Implementation idea

• Extend the current Group class to support child groups via thenBy()
• Add recursive rendering for nested collapsible sections
• Support lazy loading and per-level summaries
• Keep full backward compatibility

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Contributor note

I’d be happy to work on this and open a PR.
Tagging @danharrin to check if this idea fits the project roadmap before starting.