Files
greptimedb/src/common/function/src/scalars/math.rs
LFC dee76f0a73 refactor: simplify udf (#5617)
* refactor: simplify udf

* fix tests
2025-03-03 05:52:44 +00:00

90 lines
2.9 KiB
Rust

// Copyright 2023 Greptime Team
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
mod clamp;
mod modulo;
mod pow;
mod rate;
use std::fmt;
use std::sync::Arc;
pub use clamp::ClampFunction;
use common_query::error::{GeneralDataFusionSnafu, Result};
use common_query::prelude::Signature;
use datafusion::error::DataFusionError;
use datafusion::logical_expr::Volatility;
use datatypes::prelude::ConcreteDataType;
use datatypes::vectors::VectorRef;
pub use pow::PowFunction;
pub use rate::RateFunction;
use snafu::ResultExt;
use crate::function::{Function, FunctionContext};
use crate::function_registry::FunctionRegistry;
use crate::scalars::math::modulo::ModuloFunction;
pub(crate) struct MathFunction;
impl MathFunction {
pub fn register(registry: &FunctionRegistry) {
registry.register(Arc::new(ModuloFunction));
registry.register(Arc::new(PowFunction));
registry.register(Arc::new(RateFunction));
registry.register(Arc::new(RangeFunction));
registry.register(Arc::new(ClampFunction));
}
}
/// `RangeFunction` will never be used as a normal function,
/// just for datafusion to generate logical plan for RangeSelect
#[derive(Clone, Debug, Default)]
struct RangeFunction;
impl fmt::Display for RangeFunction {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "RANGE_FN")
}
}
impl Function for RangeFunction {
fn name(&self) -> &str {
"range_fn"
}
// The first argument to range_fn is the expression to be evaluated
fn return_type(&self, input_types: &[ConcreteDataType]) -> Result<ConcreteDataType> {
input_types
.first()
.cloned()
.ok_or(DataFusionError::Internal(
"No expr found in range_fn".into(),
))
.context(GeneralDataFusionSnafu)
}
/// `range_fn` will never been used. As long as a legal signature is returned, the specific content of the signature does not matter.
/// In fact, the arguments loaded by `range_fn` are very complicated, and it is difficult to use `Signature` to describe
fn signature(&self) -> Signature {
Signature::variadic_any(Volatility::Immutable)
}
fn eval(&self, _func_ctx: &FunctionContext, _columns: &[VectorRef]) -> Result<VectorRef> {
Err(DataFusionError::Internal(
"range_fn just a empty function used in range select, It should not be eval!".into(),
))
.context(GeneralDataFusionSnafu)
}
}