Following the SASI creation docs on Datastax (here) for DSE v5.0.4, produces the error:
cqlsh:sandbox> SHOW VERSION
[cqlsh 5.0.1 | Cassandra 3.0.10.1443 | DSE 5.0.4 | CQL spec 3.4.0 | Native protocol v4]
cqlsh:sandbox> CREATE CUSTOM INDEX "sandboxTestIdx" on test (bop) USING 'org.apache.cassandra.index.sasi.SASIIndex';
ConfigurationException: Unable to find custom indexer class 'org.apache.cassandra.index.sasi.SASIIndex'
Digging into SASI shows that it's only available 'out of the box' for Cassandra versions past 3.4, so my question is, how can I add SASI support to the latest version of DSE (v5.0.4)?
I don't think you can unless datastax releases a new version which uses cassandra 3.4 or later.
Or you can use the download the latest version of cassandra which support SASI but then you dont get the DSE features.