gabotechs commented on code in PR #20292: URL: https://github.com/apache/datafusion/pull/20292#discussion_r2845000962
########## datafusion/core/tests/statistics/mod.rs: ########## @@ -0,0 +1,161 @@ +// 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 datafusion::common::Result; +use datafusion::physical_plan::ExecutionPlan; +use datafusion_common::Statistics; +use datafusion_common::stats::Precision; +use datafusion_physical_expr_common::metrics::MetricValue; +use std::fmt::{Debug, Display, Formatter}; +use std::sync::Arc; + +mod tpcds; + +#[derive(Debug, Default, Copy, Clone)] +struct StatsVsMetricsDisplayOptions { + display_output_rows: bool, + display_output_bytes: bool, +} + +struct Node { + name: String, + stats: Statistics, + output_rows: Option<usize>, + output_bytes: Option<usize>, + children: Vec<Node>, + opts: StatsVsMetricsDisplayOptions, +} + +impl Debug for Node { + fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result { + fn fmt(f: &mut Formatter<'_>, node: &Node, depth: usize) -> std::fmt::Result { + for _ in 0..depth { + write!(f, " ")?; + } + write!(f, "{}:", node.name)?; + fn display_opt<T: Display>(opt: Option<T>) -> impl Display { + match opt { + None => "?".to_string(), + Some(v) => v.to_string(), + } + } + if node.opts.display_output_rows { + write!( + f, + " output_rows={} vs {} ({}%)", + node.stats.num_rows, + display_opt(node.output_rows), + display_opt(accuracy_percent(node.stats.num_rows, node.output_rows)) + )?; + } + if node.opts.display_output_bytes { + write!( + f, + " output_bytes={} vs {} ({}%)", + node.stats.total_byte_size, + display_opt(node.output_bytes), + display_opt(accuracy_percent( + node.stats.total_byte_size, + node.output_bytes + )) + )?; + } + writeln!(f)?; + for c in &node.children { + fmt(f, c, depth + 1)?; + } + Ok(()) + } + + fmt(f, self, 0) + } +} + +impl Node { + fn from_plan( + plan: &Arc<dyn ExecutionPlan>, + opts: StatsVsMetricsDisplayOptions, + ) -> Result<Self> { + let mut children = vec![]; + for child in plan.children() { + children.push(Node::from_plan(child, opts)?); + } + + let mut node = Node { + name: plan.name().to_string(), + stats: plan.partition_statistics(None)?, + output_rows: None, + output_bytes: None, + children, + opts, + }; + if let Some(metrics) = plan.metrics() { + node.output_rows = metrics.output_rows(); + node.output_bytes = metrics + .sum(|v| matches!(v.value(), MetricValue::OutputBytes(_))) + .map(|v| v.as_usize()); + } + + Ok(node) + } + + fn avg_row_accuracy(&self) -> usize { + fn collect_accuracy(node: &Node) -> Vec<usize> { + let mut results = vec![]; + for child in &node.children { + results.extend(collect_accuracy(child)); + } + if let Some(accuracy) = + accuracy_percent(node.stats.num_rows, node.output_rows) + { + results.push(accuracy); + } + results + } + let accuracy = collect_accuracy(self); + accuracy.iter().sum::<usize>() / accuracy.len() + } + + fn avg_byte_accuracy(&self) -> usize { + fn collect_accuracy(node: &Node) -> Vec<usize> { + let mut results = vec![]; + for child in &node.children { + results.extend(collect_accuracy(child)); + } + if let Some(accuracy) = + accuracy_percent(node.stats.total_byte_size, node.output_bytes) + { + results.push(accuracy); + } + results + } + let accuracy = collect_accuracy(self); + accuracy.iter().sum::<usize>() / accuracy.len() + } +} + +fn accuracy_percent(estimated: Precision<usize>, actual: Option<usize>) -> Option<usize> { + match (estimated.get_value(), actual) { + (Some(estimated), Some(actual)) => { + let err = (100 * estimated.abs_diff(actual)) / actual.max(*estimated).max(1); + Some(100 - err) + } + (Some(_estimated), None) => None, Review Comment: Pretty much all nodes in DataFusion are already measuring the output rows. There's a mechanism in place for doing it pretty automatically, so I think it's fair to assume that all nodes measure output rows. It's also fine to get panics because of div by zero, here, as this will only run in tests. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
