reifydb_core/value/column/view/
group_by.rs

1// Copyright (c) reifydb.com 2025
2// This file is licensed under the AGPL-3.0-or-later, see license.md file
3
4use indexmap::IndexMap;
5use reifydb_type::{Value, diagnostic::engine, error};
6
7use crate::value::column::{ColumnData, Columns};
8
9pub type GroupKey = Vec<Value>;
10pub type GroupByView = IndexMap<GroupKey, Vec<usize>>;
11
12impl Columns {
13	pub fn group_by_view(&self, keys: &[&str]) -> crate::Result<GroupByView> {
14		let row_count = self.first().map_or(0, |c| c.data().len());
15
16		let mut key_columns: Vec<&ColumnData> = Vec::with_capacity(keys.len());
17
18		for &key in keys {
19			let column = self
20				.iter()
21				.find(|c| c.name() == key)
22				.ok_or_else(|| error!(engine::frame_error(format!("Column '{}' not found", key))))?;
23			key_columns.push(&column.data());
24		}
25
26		let mut result = GroupByView::new();
27
28		for row_numberx in 0..row_count {
29			let mut values = Vec::with_capacity(keys.len());
30
31			for col in &key_columns {
32				let value = col.get_value(row_numberx);
33				values.push(value);
34			}
35
36			result.entry(values).or_default().push(row_numberx);
37		}
38
39		Ok(result)
40	}
41}