Since May 2020 empty strings are allowed in DynamoDB as attribute values (see announcment in [1]). However, they are still not allowed as keys. We had tests that they are not allowed in keys of LSI or GSI, but missed tests that they are not allowed as keys (partition or sort key) of base tables. This patch add these missing tests. These tests pass - we already had code that checked for empty keys and generated an appropriate error. Note that for compatibility with DynamoDB, Alternator will forbid empty strings as keys even though Scylla *does* support this possibility (Scylla always supported empty strings as clustering key, and empty partition keys will become possible with issue #9352). [1] https://aws.amazon.com/about-aws/whats-new/2020/05/amazon-dynamodb-now-supports-empty-values-for-non-key-string-and-binary-attributes-in-dynamodb-tables/ Signed-off-by: Nadav Har'El <nyh@scylladb.com> Message-Id: <20211003122842.471001-1-nyh@scylladb.com>