Cassandra Spark connector does not return any result when running on a single node cluster -

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i using dse 5.0.0. created following table on single node cassandra cluster:

create table if not exists dummy (   id uuid,   txt text,   primary key (id) );  insert dummy(id, txt) values (uuid(), 'hello world');

then when query specific id using spark cassandra connector, not result:

val df = sqlc.read.format("org.apache.spark.sql.cassandra")          .options(map("table" -> "mytable", "keyspace" -> "myks"))          .load()  df.show(false)  // +------------------------------------+-----------+ // |id                                  |txt        | // +------------------------------------+-----------+ // |2b69ddc1-2c15-485d-a30f-1b2d7f86c200|hello world| // +------------------------------------+-----------+  df.filter("id = '2b69ddc1-2c15-485d-a30f-1b2d7f86c200'").show  // 16/07/28 08:51:43 debug cassandratablescanrdd: fetching data range (token("id") <= ?,list(-9223372036854775808)) select "id", "txt" "myks"."mytable" token("id") <= ? , "id" = ?   allow filtering params [-9223372036854775808,2b69ddc1-2c15-485d-a30f-1b2d7f86c200] // +---+---+ // | id|txt| // +---+---+ // +---+---+

it looks query generated connector generates following bad predicate:

     token("id") <= long.minvalue

by setting few breakpoints, found out metadata built cassandra driver intentionaly sets tokenrange ]mintoken, mintoken]:

// com.datastax.driver.core.metadata, line 671     private static set<tokenrange> maketokenranges(list<token> ring, token.factory factory) {         immutableset.builder<tokenrange> builder = immutableset.builder();         // java-684: if there 1 token, return range ]mintoken, mintoken]         if (ring.size() == 1) {             builder.add(new tokenrange(factory.mintoken(), factory.mintoken(), factory));

if modify driver's code above return ]mintoken, ring(0)], dataframe returns expected result. bug in cassandra driver and/or connector, or doing wrong ?


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