reifydb_routine/function/math/
count.rs

1// SPDX-License-Identifier: Apache-2.0
2// Copyright (c) 2025 ReifyDB
3
4use std::mem;
5
6use indexmap::IndexMap;
7use reifydb_core::value::column::{
8	ColumnWithName,
9	buffer::ColumnBuffer,
10	columns::Columns,
11	view::group_by::{GroupByView, GroupKey},
12};
13use reifydb_type::value::{
14	Value,
15	r#type::{Type, input_types::InputTypes},
16};
17
18use crate::routine::{
19	Accumulator, Function, FunctionKind, Routine, RoutineInfo, context::FunctionContext, error::RoutineError,
20};
21
22pub struct Count {
23	info: RoutineInfo,
24}
25
26impl Default for Count {
27	fn default() -> Self {
28		Self::new()
29	}
30}
31
32impl Count {
33	pub fn new() -> Self {
34		Self {
35			info: RoutineInfo::new("math::count"),
36		}
37	}
38}
39
40impl<'a> Routine<FunctionContext<'a>> for Count {
41	fn info(&self) -> &RoutineInfo {
42		&self.info
43	}
44
45	fn return_type(&self, _input_types: &[Type]) -> Type {
46		Type::Int8
47	}
48
49	fn accepted_types(&self) -> InputTypes {
50		InputTypes::any()
51	}
52
53	fn propagates_options(&self) -> bool {
54		false
55	}
56
57	fn execute(&self, ctx: &mut FunctionContext<'a>, args: &Columns) -> Result<Columns, RoutineError> {
58		let row_count = args.row_count();
59		let mut counts = vec![0i64; row_count];
60
61		for col in args.iter() {
62			for (i, count) in counts.iter_mut().enumerate().take(row_count) {
63				if col.data().is_defined(i) {
64					*count += 1;
65				}
66			}
67		}
68
69		Ok(Columns::new(vec![ColumnWithName::new(ctx.fragment.clone(), ColumnBuffer::int8(counts))]))
70	}
71}
72
73impl Function for Count {
74	fn kinds(&self) -> &[FunctionKind] {
75		&[FunctionKind::Scalar, FunctionKind::Aggregate]
76	}
77
78	fn accumulator(&self, _ctx: &mut FunctionContext<'_>) -> Option<Box<dyn Accumulator>> {
79		Some(Box::new(CountAccumulator::new()))
80	}
81}
82
83struct CountAccumulator {
84	pub counts: IndexMap<GroupKey, i64>,
85}
86
87impl CountAccumulator {
88	pub fn new() -> Self {
89		Self {
90			counts: IndexMap::new(),
91		}
92	}
93}
94
95impl Accumulator for CountAccumulator {
96	fn update(&mut self, args: &Columns, groups: &GroupByView) -> Result<(), RoutineError> {
97		let column = &args[0];
98		let column_name = args.name_at(0);
99
100		let is_count_star = column_name.text() == "dummy" && matches!(column, ColumnBuffer::Int4(_));
101
102		if is_count_star {
103			for (group, indices) in groups.iter() {
104				let count = indices.len() as i64;
105				*self.counts.entry(group.clone()).or_insert(0) += count;
106			}
107		} else {
108			for (group, indices) in groups.iter() {
109				let count = indices.iter().filter(|&i| column.is_defined(*i)).count() as i64;
110				*self.counts.entry(group.clone()).or_insert(0) += count;
111			}
112		}
113		Ok(())
114	}
115
116	fn finalize(&mut self) -> Result<(Vec<GroupKey>, ColumnBuffer), RoutineError> {
117		let mut keys = Vec::with_capacity(self.counts.len());
118		let mut data = ColumnBuffer::int8_with_capacity(self.counts.len());
119
120		for (key, count) in mem::take(&mut self.counts) {
121			keys.push(key);
122			data.push_value(Value::Int8(count));
123		}
124
125		Ok((keys, data))
126	}
127}
reifydb_routine/function/math/count.rs

reifydb_routine/function/math/
count.rs
