[ 
https://issues.apache.org/jira/browse/SPARK-9340?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Cheng Lian updated SPARK-9340:
------------------------------
    Description: 
SPARK-6776 and SPARK-6777 followed {{parquet-avro}} to implement 
backwards-compatibility rules defined in {{parquet-format}} spec. However, both 
Spark SQL and {{parquet-avro}} neglected the following statement in 
{{parquet-format}}:
{quote}
This does not affect repeated fields that are not annotated: A repeated field 
that is neither contained by a {{LIST}}- or {{MAP}}-annotated group nor 
annotated by {{LIST}} or {{MAP}} should be interpreted as a required list of 
required elements where the element type is the type of the field.
{quote}
One of the consequences is that, Parquet files generated by 
{{parquet-protobuf}} containing unannotated repeated fields are not correctly 
converted to Catalyst arrays.

For example, the following Parquet schema
{noformat}
message root {
  repeated int32 f1
}
{noformat}
 should be converted to
{noformat}
StructType(StructField("f1", ArrayType(IntegerType, containsNull = false), 
nullable = false) :: Nil)
{noformat}
But now it triggers an {{AnalysisException}}.

  was:
The way ParquetTypesConverter handles primitive repeated types results in an 
incompatible schema being used for querying data. For example, given a schema 
like so:
message root {
   repeated int32 repeated_field;
 }

Spark produces a read schema like:
message root {
   optional int32 repeated_field;
 }

These are incompatible and all attempts to read fail.
In ParquetTypesConverter.toDataType:

 if (parquetType.isPrimitive) {
      toPrimitiveDataType(parquetType.asPrimitiveType, isBinaryAsString, 
isInt96AsTimestamp)
    } else {...}

The if condition should also have !parquetType.isRepetition(Repetition.REPEATED)
 
And then this case will need to be handled in the else 


> CatalystSchemaConverter and CatalystRowConverter don't handle unannotated 
> repeated fields correctly
> ---------------------------------------------------------------------------------------------------
>
>                 Key: SPARK-9340
>                 URL: https://issues.apache.org/jira/browse/SPARK-9340
>             Project: Spark
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 1.2.0, 1.3.0, 1.4.0, 1.5.0
>            Reporter: Damian Guy
>         Attachments: ParquetTypesConverterTest.scala
>
>
> SPARK-6776 and SPARK-6777 followed {{parquet-avro}} to implement 
> backwards-compatibility rules defined in {{parquet-format}} spec. However, 
> both Spark SQL and {{parquet-avro}} neglected the following statement in 
> {{parquet-format}}:
> {quote}
> This does not affect repeated fields that are not annotated: A repeated field 
> that is neither contained by a {{LIST}}- or {{MAP}}-annotated group nor 
> annotated by {{LIST}} or {{MAP}} should be interpreted as a required list of 
> required elements where the element type is the type of the field.
> {quote}
> One of the consequences is that, Parquet files generated by 
> {{parquet-protobuf}} containing unannotated repeated fields are not correctly 
> converted to Catalyst arrays.
> For example, the following Parquet schema
> {noformat}
> message root {
>   repeated int32 f1
> }
> {noformat}
>  should be converted to
> {noformat}
> StructType(StructField("f1", ArrayType(IntegerType, containsNull = false), 
> nullable = false) :: Nil)
> {noformat}
> But now it triggers an {{AnalysisException}}.



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