BloomFilter(mapping=None, *, ignore_unknown_fields=False, **kwargs)
A bloom filter (https://en.wikipedia.org/wiki/Bloom_filter).
The bloom filter hashes the entries with MD5 and treats the resulting 128-bit hash as 2 distinct 64-bit hash values, interpreted as unsigned integers using 2's complement encoding.
These two hash values, named h1
and h2
, are then used to
compute the hash_count
hash values using the formula, starting
at i=0
:
::
h(i) = h1 + (i * h2)
These resulting values are then taken modulo the number of bits in the bloom filter to get the bits of the bloom filter to test for the given entry.
Attributes |
|
---|---|
Name | Description |
bits |
google.cloud.firestore_v1.types.BitSequence
The bloom filter data. |
hash_count |
int
The number of hashes used by the algorithm. |