Pageable hash index for document store

A system comprising:

• at least one programmable processor;
• and
• a non-transitory machine-readable medium storing instructions that, when executed by the at least one programmable processor, cause the at least one programmable processor to perform operations comprising:
• generating a hash map index for data stored on disk using a document array, wherein the hash map index comprises a plurality of buckets, each bucket in the plurality of buckets storing one or more hash values of a plurality of hash values included in the hash map index, wherein each bucket is determined using significant bits of hash values stored by a respective bucket, wherein each hash value in the plurality of hash values identifies a document stored at a predetermined location in the document array, and wherein a size of the hash map index is determined as a modulo of a size of the document array;
• receiving a transaction for execution using a first document stored in the document array;
• identifying, using the generated hash map index, significant bits of a corresponding bucket and the size of the hash map index, a location of the first document stored in the document array;
• loading, into a memory location, a portion of a first hash value of the hash map index identified by the significant bits of the corresponding bucket storing the first hash value and corresponding to the first document without loading remaining hashes of the hash map index not identified by the significant bits;
• and
• executing, based on the portion of the first hash value, the transaction.

A computer program product comprising a non-transitory machine-readable medium storing instructions that, when executed by at least one programmable processor, cause the at least one programmable processor to perform operations comprising:

• generating a hash map index for data stored on disk using a document array, wherein the hash map index comprises a plurality of buckets, each bucket in the plurality of buckets storing one or more hash values of a plurality of hash values included in the hash map index, wherein each bucket is determined using significant bits of hash values stored by a respective bucket, wherein each hash value in the plurality of hash values identifies a document stored at a predetermined location in the document array, and wherein a size of the hash map index is determined as a modulo of a size of the document array;
• receiving a transaction for execution using a first document stored in the document array;
• identifying, using the generated hash map index, significant bits of a corresponding bucket and the size of the hash map index, a location of the first document stored in the document array;
• loading, into a memory location, a portion of a first hash value of the hash map index identified by the significant bits of the corresponding bucket storing the first hash value and corresponding to the first document without loading remaining hashes of the hash map index not identified by the significant bits;
• and
• executing, based on the portion of the first hash value, the transaction.