MakeKVChecksum creates a new KVChecksum with the given checksum.

NewKVChecksum creates a pointer to zero KVChecksum.

NewKVChecksumWithKeyspace creates a new KVChecksum with the given checksum and keyspace.

NewKVGroupChecksumForAdd creates a new KVGroupChecksum, and it can't be used with UpdateOneDataKV or UpdateOneIndexKV.

NewKVGroupChecksumWithKeyspace creates a new KVGroupChecksum with the given keyspace.

DataKVGroupID represents the ID for data KV group, as index id starts from 1, so we use -1 to represent data kv group.

KVChecksum is the checksum of a collection of key-value pairs.

KVGroupChecksum is KVChecksum(s) each for a data KV group or index KV groups.