IDSET

This section contains reference documentation for the IDSET function.

Returns a serialized IdSet representing the set of distinct values for a column. The IdSet can be backed by a RoaringBitmap (for INT columns), Roaring64NavigableMap (for LONG columns), or BloomFilter (for other types). The serialized IdSet is useful with the IN_ID_SET filter for efficient precomputed filtering.

Optional parameters can configure the IdSet type and properties.

Signature

IDSET(colName)

IDSET(colName, 'parameters')

Supported parameters (semicolon-separated):

Parameter	Description	Default
sizeThresholdInBytes	Maximum size before switching to BloomFilter	8MB
expectedInsertions	Expected number of insertions for BloomFilter	5000000
fpp	False positive probability for BloomFilter	0.03

Usage Examples

These examples are based on the Batch Quick Start.

select IDSET(playerID) AS value
from baseballStats
WHERE yearID = 2000

select IDSET(playerID, 'sizeThresholdInBytes=1048576;expectedInsertions=5000000;fpp=0.03') AS value
from baseballStats

The resulting IdSet can be used in subsequent queries:

select playerName
from baseballStats
WHERE IN_ID_SET(playerID, '<base64-encoded-idset>') = 1