anchor.diff:                          "field": "txId"
                       },
                       {
  -                        "type": "int64",
  +                        "type": "string",
                           "optional": true,
                           "field": "scn"
                       },
                       {
  -                        "type": "int64",
  +                        "type": "string",
                           "optional": true,
                           "field": "commit_scn"
                       },
  
positive.code:             "name": "server1",
              "ts_ms": 1520085154000,
              "txId": "6.28.807",
              "scn": 2122185,
              "commit_scn": 2122185,
              "snapshot": false
          },
          "op": "c",
  
negative.code:             "name": "server1",
              "ts_ms": 1520085811000,
              "txId": "6.9.809",
              "scn": "2125544",
              "commit_scn": "2125544",
              "snapshot": false
          },
          "op": "u",
  