[SPARK-8566] lateral view query blows up unless pushed down to a subquery

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Incomplete
• Affects Version/s: 1.4.0
• Component/s: Spark Core
• Labels: bulk-closed sparksql
• Assignee: Unassigned
• Reporter: Eric Friedman
• Created: 23/Jun/15 16:42
• Updated: 21/May/19 04:32
• Resolved: 21/May/19 04:32

Description

I have a query which works in Hive but not in SparkSQL against the same Hive metastore unless I introduce a subquery:

select col from table
lateral view explode(map_keys(col_map)) t1 as col

parquet.io.ParquetDecodingException: Can not read value at 0 in block -1 in file hdfs://nameservice1/path/to/parquet.gz
at parquet.hadoop.InternalParquetRecordReader.nextKeyValue(InternalParquetRecordReader.java:213)
at parquet.hadoop.ParquetRecordReader.nextKeyValue(ParquetRecordReader.java:204)
at org.apache.spark.sql.sources.SqlNewHadoopRDD$$anon$1.hasNext(SqlNewHadoopRDD.scala:163)
at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:39)

but if I rewrite it like so, it works:

select col from (select map_keys(col_map) keys from table) t2 lateral view explode(t2.keys) t1 as col

Issue Links

• relates to: SPARK-6489 Optimize lateral view with explode to not read unnecessary columns