Minor: Log TPCH benchmark results (apache#6813)

Author: alamb

benchmarks/Cargo.toml

@@ -37,6 +37,7 @@ arrow = { workspace = true }
 datafusion = { path = "../datafusion/core", version = "27.0.0" }
 env_logger = "0.10"
 futures = "0.3"
+log = "^0.4"
 mimalloc = { version = "0.1", optional = true, default-features = false }
 num_cpus = "1.13.0"
 parquet = { workspace = true }

benchmarks/src/bin/tpch.rs

@@ -16,7 +16,9 @@
 // under the License.
 
 //! Benchmark derived from TPC-H. This is not an official TPC-H benchmark.
+use log::info;
 
+use arrow::util::pretty::pretty_format_batches;
 use datafusion::datasource::file_format::{csv::CsvFormat, FileFormat};
 use datafusion::datasource::{MemTable, TableProvider};
 use datafusion::error::{DataFusionError, Result};
@@ -235,6 +237,7 @@ async fn benchmark_query(
         let elapsed = start.elapsed(); //.as_secs_f64() * 1000.0;
         let ms = elapsed.as_secs_f64() * 1000.0;
         millis.push(ms);
+        info!("output:\n\n{}\n\n", pretty_format_batches(&result)?);
         let row_count = result.iter().map(|b| b.num_rows()).sum();
         println!(
             "Query {query_id} iteration {i} took {ms:.1} ms and returned {row_count} rows"