mapleFU commented on code in PR #207: URL: https://github.com/apache/kvrocks-website/pull/207#discussion_r1518561809
########## community/data-structure-on-rocksdb.md: ########## @@ -314,3 +315,28 @@ where the `payload` is a string encoded in the corresponding `format`: | CBOR | 1 | Also, if we decide to add a more IO-friendly format to avoid reading all payload to the memory before searching an element via JSONPath or seperate a relatively large JSON to multiple key-values, we can take advantage of the `format` field. + +## Hyperloglog + +Redis hyperloglog can be thought of as a static array with a length of 16384. The array elements are called registers, which are used to store the maximum count of consecutive 0s. This register array is the input parameter for the hyperloglog algorithm. +In Kvrocks, the hyperloglog data structure is stored in following two parts: + +#### hyperloglog metadata + +```text + +----------+------------+-----------+-----------+ +key => | flags | expire | version | size | + | (1byte) | (Ebyte) | (8byte) | (Sbyte) | + +----------+------------+-----------+-----------+ +``` +- `size` records the number of registers, which is a constant, even no element is added. + +#### hyperloglog sub keys-values Review Comment: Would you mind try Bitmap structure? "bitfield" command might help in this case? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
