private static Set<List<Comparable<?>>> getPartitionKeysSet(
CassandraTable table, TupleDomain<ColumnHandle> tupleDomain) {
ImmutableList.Builder<Set<Comparable<?>>> partitionColumnValues = ImmutableList.builder();
for (CassandraColumnHandle columnHandle : table.getPartitionKeyColumns()) {
Domain domain = tupleDomain.getDomains().get(columnHandle);
// if there is no constraint on a partition key, return an empty set
if (domain == null) {
return ImmutableSet.of();
}
// todo does cassandra allow null partition keys?
if (domain.isNullAllowed()) {
return ImmutableSet.of();
}
ImmutableSet.Builder<Comparable<?>> columnValues = ImmutableSet.builder();
for (Range range : domain.getRanges()) {
// if the range is not a single value, we can not perform partition pruning
if (!range.isSingleValue()) {
return ImmutableSet.of();
}
Comparable<?> value = range.getSingleValue();
CassandraType valueType = columnHandle.getCassandraType();
columnValues.add(valueType.getValueForPartitionKey(value));
}
partitionColumnValues.add(columnValues.build());
}
return Sets.cartesianProduct(partitionColumnValues.build());
}
