Legacy mapping of Solr types 

Legacy mapping of Solr types is requires if you created indexes in DataStax Enterprise 3.0.x or earlier. DataStax Enterprise 3.0.x and earlier use the legacy type mapping by default.

Configure legacy mapping of Solr types if you created indexes in DataStax Enterprise 3.0.x or earlier. DataStax Enterprise 3.0.x and earlier use the legacy type mapping by default.

Solr Type Cassandra Validator
TextField UTF8Type
StrField UTF8Type
LongField LongType
IntField Int32Type
FloatField FloatType
DoubleField DoubleType
DateField UTF8Type
ByteField BytesType
BinaryField BytesType
BoolField UTF8Type
UUIDField UUIDType
TrieDateField UTF8Type
TrieDoubleField UTF8Type
TrieField UTF8Type
TrieFloatField UTF8Type
TrieIntField UTF8Type
TrieLongField UTF8Type
All Others UTF8Type

If you use legacy type mappings, the solr schema needs to define the unique key as a string.