razeghi71 commented on code in PR #8446: URL: https://github.com/apache/arrow-datafusion/pull/8446#discussion_r1421247873
########## datafusion/physical-plan/src/placeholder_row.rs: ########## @@ -0,0 +1,229 @@ +// 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. + +//! EmptyRelation produce_one_row=true execution plan + +use std::any::Any; +use std::sync::Arc; + +use super::expressions::PhysicalSortExpr; +use super::{common, DisplayAs, SendableRecordBatchStream, Statistics}; +use crate::{memory::MemoryStream, DisplayFormatType, ExecutionPlan, Partitioning}; + +use arrow::array::{ArrayRef, NullArray}; +use arrow::datatypes::{DataType, Field, Fields, Schema, SchemaRef}; +use arrow::record_batch::RecordBatch; +use datafusion_common::{internal_err, DataFusionError, Result}; +use datafusion_execution::TaskContext; + +use log::trace; + +/// Execution plan for empty relation with produce_one_row=true +#[derive(Debug)] +pub struct PlaceholderRowExec { + /// The schema for the produced row + schema: SchemaRef, + /// Number of partitions + partitions: usize, +} + +impl PlaceholderRowExec { + /// Create a new PlaceholderRowExec + pub fn new(schema: SchemaRef) -> Self { + PlaceholderRowExec { + schema, + partitions: 1, + } + } + + /// Create a new PlaceholderRowExecPlaceholderRowExec with specified partition number + pub fn with_partitions(mut self, partitions: usize) -> Self { + self.partitions = partitions; + self + } + + fn data(&self) -> Result<Vec<RecordBatch>> { + Ok({ + let n_field = self.schema.fields.len(); Review Comment: It does, In this case for example: ```sql CREATE TABLE test (c INT) as values(0); SELECT COUNT(*) from test; ``` -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
