Aman Sinha created DRILL-1834: --------------------------------- Summary: Misleading error message when querying an empty Parquet file Key: DRILL-1834 URL: https://issues.apache.org/jira/browse/DRILL-1834 Project: Apache Drill Issue Type: Bug Components: Execution - Flow Affects Versions: 0.7.0 Reporter: Aman Sinha
It is possible that a CTAS may fail and create an empty Parquet file. When we run a query against this file, we get a misleading error message from the planner that hides the original IOException, although the log file does have the original exception: {code:sql} 0: jdbc:drill:zk=local> select count(*) from dfs.`/tmp/empty.parquet`; Query failed: Query failed: Unexpected exception during fragment initialization: Internal error: Error while applying rule DrillPushProjIntoScan, args [rel#77:ProjectRel.NONE.ANY([]).[](child=rel#76:Subset#0.ENUMERABLE.ANY([]).[],$f0=0), rel#68:EnumerableTableAccessRel.ENUMERABLE.ANY([]).[](table=[dfs, /tmp/empty.parquet])] {code} The cause of the exception is in the logs: Caused by: java.io.IOException: Could not read footer: java.lang.RuntimeException: file:/tmp/empty.parquet is not a Parquet file (too small) at parquet.hadoop.ParquetFileReader.readAllFootersInParallel(ParquetFileReader.java:195) ~[parquet-hadoop-1.5.1-drill-r4.jar:0.7.0-SNAPSHOT] at parquet.hadoop.ParquetFileReader.readAllFootersInParallel(ParquetFileReader.java:208) ~[parquet-hadoop-1.5.1-drill-r4.jar:0.7.0-SNAPSHOT] at parquet.hadoop.ParquetFileReader.readFooters(ParquetFileReader.java:224) ~[parquet-hadoop-1.5.1-drill-r4.jar:0.7.0-SNAPSHOT] at org.apache.drill.exec.store.parquet.ParquetGroupScan.readFooter(ParquetGroupScan.java:208) ~[drill-java-exec-0.7.0-SNAPSHOT-rebuffed.jar:0.7.0-SNAPSHOT] -- This message was sent by Atlassian JIRA (v6.3.4#6332)