velvia commented on a change in pull request #9376: URL: https://github.com/apache/arrow/pull/9376#discussion_r575728461
########## File path: rust/datafusion/src/physical_plan/expressions/nullif.rs ########## @@ -0,0 +1,188 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you 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. + +use std::sync::Arc; + +use super::ColumnarValue; +use crate::error::{DataFusionError, Result}; +use crate::scalar::ScalarValue; +use arrow::array::Array; +use arrow::array::{ + ArrayRef, BooleanArray, Date32Array, Date64Array, Float32Array, Float64Array, + Int16Array, Int32Array, Int64Array, Int8Array, StringArray, TimestampNanosecondArray, + UInt16Array, UInt32Array, UInt64Array, UInt8Array, +}; +use arrow::compute::kernels::boolean::nullif; +use arrow::compute::kernels::comparison::{eq, eq_scalar, eq_utf8, eq_utf8_scalar}; +use arrow::datatypes::{DataType, TimeUnit}; + +/// Invoke a compute kernel on a primitive array and a Boolean Array +macro_rules! compute_bool_array_op { + ($LEFT:expr, $RIGHT:expr, $OP:ident, $DT:ident) => {{ + let ll = $LEFT + .as_any() + .downcast_ref::<$DT>() + .expect("compute_op failed to downcast array"); + let rr = $RIGHT + .as_any() + .downcast_ref::<BooleanArray>() + .expect("compute_op failed to downcast array"); + Ok(Arc::new($OP(&ll, &rr)?) as ArrayRef) + }}; +} + +/// Binary op between primitive and boolean arrays +macro_rules! primitive_bool_array_op { + ($LEFT:expr, $RIGHT:expr, $OP:ident) => {{ + match $LEFT.data_type() { + DataType::Int8 => compute_bool_array_op!($LEFT, $RIGHT, $OP, Int8Array), + DataType::Int16 => compute_bool_array_op!($LEFT, $RIGHT, $OP, Int16Array), + DataType::Int32 => compute_bool_array_op!($LEFT, $RIGHT, $OP, Int32Array), + DataType::Int64 => compute_bool_array_op!($LEFT, $RIGHT, $OP, Int64Array), + DataType::UInt8 => compute_bool_array_op!($LEFT, $RIGHT, $OP, UInt8Array), + DataType::UInt16 => compute_bool_array_op!($LEFT, $RIGHT, $OP, UInt16Array), + DataType::UInt32 => compute_bool_array_op!($LEFT, $RIGHT, $OP, UInt32Array), + DataType::UInt64 => compute_bool_array_op!($LEFT, $RIGHT, $OP, UInt64Array), + DataType::Float32 => compute_bool_array_op!($LEFT, $RIGHT, $OP, Float32Array), + DataType::Float64 => compute_bool_array_op!($LEFT, $RIGHT, $OP, Float64Array), + other => Err(DataFusionError::Internal(format!( + "Unsupported data type {:?} for NULLIF/primitive/boolean operator", + other + ))), + } + }}; +} + +/// Implements NULLIF(expr1, expr2) +/// Args: 0 - left expr is any array +/// 1 - if the left is equal to this expr2, then the result is NULL, otherwise left value is passed. +/// +pub fn nullif_func(args: &[ColumnarValue]) -> Result<ColumnarValue> { + if args.len() != 2 { + return Err(DataFusionError::Internal(format!( + "{:?} args were supplied but NULLIF takes exactly two args", + args.len(), + ))); + } + + let (lhs, rhs) = (&args[0], &args[1]); + + match (lhs, rhs) { + (ColumnarValue::Array(lhs), ColumnarValue::Scalar(rhs)) => { + let cond_array = binary_array_op_scalar!(lhs, rhs.clone(), eq).unwrap()?; Review comment: This is definitely one of the functions I would expect to benefit the most from this change, given that NULLIF most of the time the right hand argument is likely to be a scalar. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
