This document walks you through how to use RawKV’s Checksum API.

Checksum API returns Crc64Xor, TotalKvs and TotalBytes from TiKV cluster.

  • Crc64Xor: The XOR of every key-value pair’s crc64 value.
  • TotalKVs: The number of key-value pairs.
  • TotalBytes: The size of key-value pairs in bytes.

Note: If API V2 is enabled, a 4 bytes prefix is encoded with keys, and also calculated by Checksum API.

Go

Checksum with range

Using the Checksum API, you can get {Crc64Xor, TotalKvs, TotalBytes} of a range from startKey (inclusive) to endKey (exclusive).

To calculate checksum of all keys, specify startKey and endKey as []byte("").

  1. package main
  3. import (
  4.     "context"
  5.     "fmt"
  7.     "github.com/pingcap/kvproto/pkg/kvrpcpb"
  8.     "github.com/tikv/client-go/v2/rawkv"
  9. )
  11. func main() {
  12.     ctx := context.TODO()
  13.     cli, err := rawkv.NewClientWithOpts(ctx, []string{"127.0.0.1:2379"},
  14.         rawkv.WithAPIVersion(kvrpcpb.APIVersion_V2))
  15.     if err != nil {
  16.         panic(err)
  17.     }
  18.     defer cli.Close()
  20.     fmt.Printf("Cluster ID: %d\n", cli.ClusterID())
  22.     // put key into tikv
  23.     cli.Put(ctx, []byte("k1"), []byte("v1"))
  24.     cli.Put(ctx, []byte("k2"), []byte("v2"))
  25.     cli.Put(ctx, []byte("k3"), []byte("v3"))
  26.     cli.Put(ctx, []byte("k4"), []byte("v4"))
  27.     cli.Put(ctx, []byte("k5"), []byte("v5"))
  29.     checksum, err := cli.Checksum(ctx, []byte("k1"), []byte("k6"))
  30.     if err != nil {
  31.         panic(err)
  32.     }
  34.     fmt.Printf("Get checksum, Crc64Xor:%d, TotalKvs:%d, TotalBytes:%d.\n",
  35.         checksum.Crc64Xor, checksum.TotalKvs, checksum.TotalBytes)
  36. }

You will get the result as following:

  1. Cluster ID: 7166545317297238572
  2. Get checksum, Crc64Xor:7402990595130313958, TotalKvs:5, TotalBytes:40.