[DRILL-1834] Misleading error message when querying an empty Parquet file

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.7.0
• Fix Version/s: 1.17.0
• Component/s: Execution - Flow
• Assignee: Unassigned
• Reporter: Aman Sinha
• Created: 10/Dec/14 00:02
• Updated: 04/Oct/19 12:37
• Resolved: 04/Oct/19 12:37

Description

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:

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])]

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]

Issue Links

• is superceded by: DRILL-4517 Reading emtpy Parquet file failes with java.lang.IllegalArgumentException