m0_61364557 2021-10-16 17:05 采纳率: 83.3%
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已结题

MySql中如何提取text类型字段中的数据,json_extract试过了,取出来的都是空值

"{"source":"self","id":"13","name":"01.mp4","length":0}"
"{"source":"self","id":"13","name":"01.mp4","length":0}"
"{"size":3556197,"length":0,"source":"self","status":"none","name":"\u662f\u662f\u662f1.mp4","id":9}"
"{"size":3869713,"length":0,"source":"self","status":"none","name":"\u662f\u662f\u662f2.mp4","id":10}"

字段类型为text,类型也不能改,

JSON_EXTRACT(( cast(字段 as josn),"$.id") 也不行,查询是空值。

如何取出字段中id对应的数字?

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1条回答 默认 最新

  • ACMAIN_CHM 2021-10-16 20:38
    关注

    你没写正确!!!

    
    mysql> desc m0_61364557;
    +-------+------+------+-----+---------+-------+
    | Field | Type | Null | Key | Default | Extra |
    +-------+------+------+-----+---------+-------+
    | m1    | text | YES  |     | NULL    |       |
    +-------+------+------+-----+---------+-------+
    1 row in set (0.02 sec)
    
    mysql> select * from m0_61364557;
    +---------------------------------------------------------------------------------------------------+
    | m1                                                                                                |
    +---------------------------------------------------------------------------------------------------+
    | {"source":"self","id":"13","name":"01.mp4","length":0}                                            |
    | {"source":"self","id":"13","name":"01.mp4","length":0}                                            |
    | {"size":3556197,"length":0,"source":"self","status":"none","name":"u662fu662fu662f1.mp4","id":9}  |
    | {"size":3869713,"length":0,"source":"self","status":"none","name":"u662fu662fu662f2.mp4","id":10} |
    +---------------------------------------------------------------------------------------------------+
    4 rows in set (0.00 sec)
    
    mysql> select JSON_EXTRACT( m1,"$.id") from m0_61364557;
    +--------------------------+
    | JSON_EXTRACT( m1,"$.id") |
    +--------------------------+
    | "13"                     |
    | "13"                     |
    | 9                        |
    | 10                       |
    +--------------------------+
    4 rows in set (0.00 sec)
    
    mysql>
    
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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问题事件

  • 系统已结题 12月14日
  • 已采纳回答 12月6日
  • 创建了问题 10月16日

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