Apache Pinot Docs
release-0.10.0
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Bloom Filter

Bloom filter helps prune segments that do not contain any record matching an EQUALITY predicate.
It would be useful for a query like the following:
SELECT COUNT(*)
FROM baseballStats
WHERE playerID = 12345
There are 3 parameters to configure the Bloom Filter:
  • fpp: False positive probability of the bloom filter (from 0 to 1, 0.05 by default). The lower the fpp , the higher accuracy the bloom filter has, but it will also increase the size of the bloom filter.
  • maxSizeInBytes: Maximum size of the bloom filter (unlimited by default). If a certain fpp generates a bloom filter larger than this size, we will increase the fpp to keep the bloom filter size within this limit.
  • loadOnHeap: Whether to load the bloom filter using heap memory or off-heap memory (false by default).
There are 2 ways to configure a bloom filter for a table in the table config:
  • Default settings
{
"tableIndexConfig": {
"bloomFilterColumns": [
"playerID",
...
],
...
},
...
}
  • Customized parameters
{
"tableIndexConfig": {
"bloomFilterConfigs": {
"playerID": {
"fpp": 0.01,
"maxSizeInBytes": 1000000,
"loadOnHeap": true
},
...
},
...
},
...
}
A Bloom Filter can only be applied to dictionary-encoded columns. Support for raw value columns is WIP.