BloomFilter¶

BloomFilter is an abstraction of bloom filters for the following:

• DataFrameStatFunctions.bloomFilter operator
• BloomFilterAggregate expression (as an aggregation buffer)
• BloomFilterMightContain expression

Contract (Subset)¶

bitSize¶

long bitSize()

See:

• BloomFilterImpl

Used when:

• BloomFilterAggregate is requested to serialize a BloomFilter

mightContain¶

boolean mightContain(
  Object item)

See:

• BloomFilterImpl

mightContainLong¶

boolean mightContainLong(
  long item)

See:

• BloomFilterImpl

Used when:

• BloomFilterImpl is requested to mightContain
• BloomFilterMightContain is requested to evaluate and doGenCode

mightContainString¶

boolean mightContainString(
  String item)

See:

• BloomFilterImpl

Used when:

• BloomFilterImpl is requested to mightContain

Implementations¶

• BloomFilterImpl

Creating BloomFilter¶

BloomFilter create(
  long expectedNumItems)
BloomFilter create(
  long expectedNumItems,
  double fpp)
BloomFilter create(
  long expectedNumItems,
  long numBits)

create creates a BloomFilterImpl for the given expectedNumItems.

Unless the False Positive Probability (fpp) is given, create uses DEFAULT_FPP value to determine the optimal number of bits.

create is used when:

• BloomFilterAggregate is requested to create an aggregation buffer
• DataFrameStatFunctions is requested to build a BloomFilter