I believe it needs needs to be VARIANT(1) , the (1) being the "specification_version" [1]
We recently fixed an example in LogicalTypes.md[2] to follow the .thrift Fixing the examples in VariantEncoding.md[3] I think would be a good change Andrew [1]: https://github.com/apache/parquet-format/blob/285b6fd1335da2e8bafe8570f0c00b55c2c41748/src/main/thrift/parquet.thrift#L412 [2]: https://github.com/apache/parquet-format/pull/555 [3]: https://github.com/apache/parquet-format/blob/master/VariantEncoding.md On Mon, Mar 30, 2026 at 9:10 AM Steve Loughran <[email protected]> wrote: > The normative specification of variants, parquet-format/VariantEncoding.md, > uses examples > > optional group shredded_variant_name (VARIANT) { > required binary metadata; > optional binary value; > optional int64 typed_value; > } > > But copy that and you get an error > > java.lang.IllegalArgumentException: Expecting only spec version for variant > annotation args: [] > at org.apache.parquet.Preconditions.checkArgument(Preconditions.java:70) > at > > org.apache.parquet.schema.LogicalTypeAnnotation$LogicalTypeToken$3.fromString(LogicalTypeAnnotation.java:64) > at > > org.apache.parquet.schema.MessageTypeParser.addGroupType(MessageTypeParser.java:139) > at > > org.apache.parquet.schema.MessageTypeParser.addType(MessageTypeParser.java:109) > at > > org.apache.parquet.schema.MessageTypeParser.addGroupTypeFields(MessageTypeParser.java:99) > at > > org.apache.parquet.schema.MessageTypeParser.parse(MessageTypeParser.java:92) > at > > org.apache.parquet.schema.MessageTypeParser.parseMessageType(MessageTypeParser.java:82) > > It has to be (VARIANT(1)), as is done in the limited number of places a > variant is declared in the code. > > Is this an omission in the specification? > > If it is, I'll file an issue/pr to fix. >
