DROP TABLE IF EXISTS `proxy_param`;
CREATE TABLE `proxy_param` (
  `proxy_id` bigint NOT NULL,
  `recommend_ids` json DEFAULT NULL,
  `photos` json DEFAULT NULL,
  PRIMARY KEY (`proxy_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

INSERT INTO `proxy_param` (`proxy_id`, `recommend_ids`, `photos`) VALUES (1, '[584, 585]', 'null');
INSERT INTO `proxy_param` (`proxy_id`, `recommend_ids`, `photos`) VALUES (2, '[]', NULL);

模型映射为: 
type ProxyParam struct {
	ProxyId               int64    `json:"proxyId"              orm:"proxy_id"              description:""`
	RecommendIds []int64  `json:"recommendIds" orm:"recommend_ids" description:""`
	Photos                []string `json:"photos"              orm:"photos"                 description:""`
}

var proxyParamList []*entity.ProxyParam
err := dao.ProxyParam.Ctx(context.Background()).Scan(&proxyParamList)
fmt.Println(err) // nil
for _, param := range proxyParamList {
fmt.Printf("%+v\n", param)
}
//遍历打印机结果1： &{ProxyId:1 RecommendIds:[584 585] Photos:[null]}， 这里反序列化结果明显错误了，null为有效的json内容，虽然和数据库的NULL有所不同，但是 json的null 转为[]string 结果应该是 []
//遍历打印机结果2： &{ProxyId:2 RecommendIds:[] Photos:[]}

var proxyId int64
err := dao.ProxyParam.Ctx(context.Background()).Where("proxy_id", 1).
Fields("proxy_id").Scan(&proxyId)
fmt.Println(err) // element of parameter "pointer" for function Scan should type of struct/*struct/[]struct/[]*struc
fmt.Println(proxyId)

var proxyIds []int64
err := dao.ProxyParam.Ctx(context.Background()).Fields("proxy_id").Scan(&proxyIds)
fmt.Println(err) // nil 
fmt.Println(proxyIds) // [0 0]  内容错误，正确值是[1 2]

var recommendIds []int64
err := dao.ProxyParam.Ctx(context.Background()).Where("proxy_id", 1).
Fields("recommend_ids").Scan(&recommendIds)
fmt.Println(err) //nil,  没有错误
fmt.Println(recommendIds) //[0]    内容错误，正确值是[584 585]