mysql字段类型json更新

update
  tbl_test
set
  test_json = JSON_REPLACE(
    test_json,
    '$."jsonFieldName"',
    (
      CAST(test_json -> '$."jsonFieldName"' AS SIGNED INTEGER) - 70 * 365 -19
    ) * 86400 - 3600 * 8
  ) 
where 
　　test_json -> '$."jsonFieldName"' = "55555"
limit
  1