The DDB table was exported from DynamoDB to S3 and I would like to run some Athena queries against the table. Table’s items have two keys (PK and pk) which are the same when they are in lowercase.
Currently tables has two items only:

{"Item":{"PK":{"S":"c#hpD_dnHyoGsgGgNdb8xq36zieC2bdz-QgEyUmVXffuw"},"SK":{"S":"VPZQ+OIh7YXE8qt+GFUoOQ==#jrZ1h4vLmvwmxBgjXoQM5w"},"pk":{"S":"4"},"dc":{"S":"28"}}}
{"Item":{"PK":{"S":"c#qf_hDkjVLu96FICbwRfsUKZqs89D3LT5dG2KrfKz_M8"},"SK":{"S":"LyQg1ehf6lJaWGis7wKPHQ==#PfG2IemA1VVjGZmHrOgKtA"},"pk":{"S":"4"},"dc":{"S":"7"}}}

I’ve read following docs how to resolve the same keys issue in Athena table

• https://repost.aws/knowledge-center/json-duplicate-key-error-athena-config
• https://docs.aws.amazon.com/athena/latest/ug/openx-json-serde.html (case.insensitive section)

and based on recommendations had created the following schema for the table with "case.insensitive" = "FALSE" property and remapping for the duplicated fields

CREATE EXTERNAL TABLE `test`(
  `item` struct<PK:struct<S:string>,pk:struct<S:string>,sk:struct<S:string>,dc:struct<S:string>>)
ROW FORMAT SERDE 
  'org.openx.data.jsonserde.JsonSerDe' 
WITH SERDEPROPERTIES ( 
  "case.insensitive" = "FALSE", 
  "mapping.pk1" = "PK", 
  "mapping.pk2" = "pk", 
  'paths'='Item') 
STORED AS INPUTFORMAT 
  'org.apache.hadoop.mapred.TextInputFormat' 
OUTPUTFORMAT 
  'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
LOCATION
  's3://bucket/310724/AWSDynamoDB/id/test/'
TBLPROPERTIES (
  'classification'='json', 
  'compressionType'='none', 
  'objectCount'='1', 
  'typeOfData'='file')

Now when I query the table to preview the data (only two rows are in the table in this moment)

SELECT * FROM "test" limit 10;

the response doesn’t show any data however returns correct number of rows in the table (two items)

#   item
1
2

When I try to query particular column I get

SELECT Item.PK.s FROM "test" limit 10;
>>> AMBIGUOUS_NAME: line 1:13: Ambiguous row field reference: PK

SELECT Item.pk.s FROM "test" limit 10;
>>> AMBIGUOUS_NAME: line 1:13: Ambiguous row field reference: pk

SELECT Item.pk2.s FROM "test" limit 10;
>>> COLUMN_NOT_FOUND: line 1:8: Column 'item.pk2' cannot be resolved or requester is not authorized to access requested resources

SELECT Item.dc.s FROM "test" limit 10;
>>> two empty rows

Any advice what I’m doing wrong?