xudong963 commented on code in PR #15503: URL: https://github.com/apache/datafusion/pull/15503#discussion_r2027374194
########## datafusion/core/tests/physical_optimizer/partition_statistics.rs: ########## @@ -0,0 +1,317 @@ +// 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. + +#[cfg(test)] +mod test { + use arrow_schema::{DataType, Field, Schema, SortOptions}; + use datafusion::datasource::listing::ListingTable; + use datafusion::prelude::SessionContext; + use datafusion_catalog::TableProvider; + use datafusion_common::stats::Precision; + use datafusion_common::{ScalarValue, Statistics}; + use datafusion_execution::config::SessionConfig; + use datafusion_expr_common::operator::Operator; + use datafusion_physical_expr::expressions::{binary, lit, Column}; + use datafusion_physical_expr_common::physical_expr::PhysicalExpr; + use datafusion_physical_expr_common::sort_expr::{LexOrdering, PhysicalSortExpr}; + use datafusion_physical_plan::filter::FilterExec; + use datafusion_physical_plan::projection::ProjectionExec; + use datafusion_physical_plan::sorts::sort::SortExec; + use datafusion_physical_plan::union::UnionExec; + use datafusion_physical_plan::ExecutionPlan; + use std::sync::Arc; + + async fn generate_listing_table_with_statistics( + target_partition: Option<usize>, + ) -> Arc<dyn ExecutionPlan> { + let mut session_config = SessionConfig::new().with_collect_statistics(true); + if let Some(partition) = target_partition { + session_config = session_config.with_target_partitions(partition); + } + let ctx = SessionContext::new_with_config(session_config); + // Create table with partition + let create_table_sql = "CREATE EXTERNAL TABLE t1 (id INT not null, date DATE) STORED AS PARQUET LOCATION './tests/data/test_statistics_per_partition' PARTITIONED BY (date) WITH ORDER (id ASC);"; + ctx.sql(create_table_sql) + .await + .unwrap() + .collect() + .await + .unwrap(); + let table = ctx.table_provider("t1").await.unwrap(); + let listing_table = table + .as_any() + .downcast_ref::<ListingTable>() + .unwrap() + .clone(); + listing_table + .scan(&ctx.state(), None, &[], None) + .await + .unwrap() + } + + fn check_unchanged_statistics(statistics: Vec<Statistics>) { + // Check the statistics of each partition + for stat in &statistics { + assert_eq!(stat.num_rows, Precision::Exact(2)); + // First column (id) should have non-null values + assert_eq!(stat.column_statistics[0].null_count, Precision::Exact(0)); + } + + // Verify specific id values for each partition + assert_eq!( + statistics[0].column_statistics[0].max_value, + Precision::Exact(ScalarValue::Int32(Some(4))) + ); + assert_eq!( + statistics[0].column_statistics[0].min_value, + Precision::Exact(ScalarValue::Int32(Some(3))) + ); + assert_eq!( + statistics[1].column_statistics[0].max_value, + Precision::Exact(ScalarValue::Int32(Some(2))) + ); + assert_eq!( + statistics[1].column_statistics[0].min_value, + Precision::Exact(ScalarValue::Int32(Some(1))) + ); + } + + #[tokio::test] + async fn test_statistics_by_partition_of_data_source() -> datafusion_common::Result<()> + { + let scan = generate_listing_table_with_statistics(Some(2)).await; + let statistics = scan.statistics_by_partition()?; + // Check the statistics of each partition + assert_eq!(statistics.len(), 2); + for stat in &statistics { + assert_eq!(stat.column_statistics.len(), 2); + assert_eq!(stat.total_byte_size, Precision::Exact(110)); + } + check_unchanged_statistics(statistics); + Ok(()) + } + + #[tokio::test] + async fn test_statistics_by_partition_of_projection() -> datafusion_common::Result<()> + { + let scan = generate_listing_table_with_statistics(Some(2)).await; + // Add projection execution plan + let exprs: Vec<(Arc<dyn PhysicalExpr>, String)> = + vec![(Arc::new(Column::new("id", 0)), "id".to_string())]; + let projection = ProjectionExec::try_new(exprs, scan)?; + let statistics = projection.statistics_by_partition()?; + for stat in &statistics { + assert_eq!(stat.column_statistics.len(), 1); + assert_eq!(stat.total_byte_size, Precision::Exact(8)); + } + check_unchanged_statistics(statistics); + Ok(()) + } + + #[tokio::test] + async fn test_statistics_by_partition_of_sort() -> datafusion_common::Result<()> { + let scan = generate_listing_table_with_statistics(Some(2)).await; + // Add sort execution plan + let sort = SortExec::new( + LexOrdering::new(vec![PhysicalSortExpr { + expr: Arc::new(Column::new("id", 0)), + options: SortOptions { + descending: false, + nulls_first: false, + }, + }]), + scan, + ); + let mut sort_exec = Arc::new(sort.clone()); + let statistics = sort_exec.statistics_by_partition()?; + assert_eq!(statistics.len(), 1); + assert_eq!(statistics[0].num_rows, Precision::Exact(4)); + assert_eq!(statistics[0].column_statistics.len(), 2); + assert_eq!(statistics[0].total_byte_size, Precision::Exact(220)); + assert_eq!( + statistics[0].column_statistics[0].null_count, + Precision::Exact(0) + ); + assert_eq!( + statistics[0].column_statistics[0].max_value, + Precision::Exact(ScalarValue::Int32(Some(4))) + ); + assert_eq!( + statistics[0].column_statistics[0].min_value, + Precision::Exact(ScalarValue::Int32(Some(1))) + ); + sort_exec = Arc::new(sort.with_preserve_partitioning(true)); + let statistics = sort_exec.statistics_by_partition()?; + assert_eq!(statistics.len(), 2); + assert_eq!(statistics[0].num_rows, Precision::Exact(2)); + assert_eq!(statistics[1].num_rows, Precision::Exact(2)); + assert_eq!(statistics[0].column_statistics.len(), 2); + assert_eq!(statistics[1].column_statistics.len(), 2); + assert_eq!(statistics[0].total_byte_size, Precision::Exact(110)); + assert_eq!(statistics[1].total_byte_size, Precision::Exact(110)); + assert_eq!( + statistics[0].column_statistics[0].null_count, + Precision::Exact(0) + ); + assert_eq!( + statistics[0].column_statistics[0].max_value, + Precision::Exact(ScalarValue::Int32(Some(4))) + ); + assert_eq!( + statistics[0].column_statistics[0].min_value, + Precision::Exact(ScalarValue::Int32(Some(3))) + ); + assert_eq!( + statistics[1].column_statistics[0].null_count, + Precision::Exact(0) + ); + assert_eq!( + statistics[1].column_statistics[0].max_value, + Precision::Exact(ScalarValue::Int32(Some(2))) + ); + assert_eq!( + statistics[1].column_statistics[0].min_value, + Precision::Exact(ScalarValue::Int32(Some(1))) + ); + Ok(()) + } + + #[tokio::test] + async fn test_statistics_by_partition_of_filter() -> datafusion_common::Result<()> { + let scan = generate_listing_table_with_statistics(Some(2)).await; + let schema = Schema::new(vec![Field::new("id", DataType::Int32, false)]); + let predicate = binary( + Arc::new(Column::new("id", 0)), + Operator::Lt, + lit(1i32), + &schema, + )?; + let filter: Arc<dyn ExecutionPlan> = + Arc::new(FilterExec::try_new(predicate, scan)?); + let _full_statistics = filter.statistics()?; + // The full statistics is invalid, at least, we can improve the selectivity estimation of the filter Review Comment: I think the result of `full_statistics` can be improved, I'll open an issue to follow the further improvement. -- This is an automated message from the Apache Git Service. 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