mysql 列转行 并进行json截取(mysql 5.6)

如为8.0以上版本，可以直接使用原生的json解析器处理，低版本不支持

set @fild='"},{"';

SELECT 
     t1.id
    ,t2.num_rn
    ,substring_index(substring_index(t1.image_file,@fild, t2.num_rn + 1), '"},{"', -1) as result -- 列转行
FROM (
    SELECT
         1 as id
        ,'[{"id":"78c34a25-c206-4e32-9dc1-082a115f4d3e","user_id":"b79bb5e1-b08c-4a05-be3e-0fb1154d925f","url":"https://img_url/mobilecheckquality/upload/d3c12032-3863-4125-83db-5caeb095bac8.jpg"},{"id":"724bc057-be95-4ba4-b0c9-4ce9623dd6ed","user_id":"b79bb5e1-b08c-4a05-be3e-0fb1154d925f","url":"https://img_url/mobilecheckquality/upload/12497eac-0033-4152-9ea7-529eb2f3f9c6.jpg"},{"id":"416cbb4f-8a16-419d-a7c6-a3d01877548b","user_id":"b79bb5e1-b08c-4a05-be3e-0fb1154d925f","url":"https://img_url/mobilecheckquality/upload/416cbb4f-8a16-419d-a7c6-a3d01877548b.jpg"},{"id":"ef56c530-cf6e-42c5-a82b-5df159732a08","user_id":"b79bb5e1-b08c-4a05-be3e-0fb1154d925f","url":"https://img_url/mobilecheckquality/upload/ef56c530-cf6e-42c5-a82b-5df159732a08.jpg"}]' as image_file
) t1
join (
    select 0 as num_rn union all
    select 1 as num_rn union all
    select 2 as num_rn union all
    select 3 as num_rn union all
    select 4 as num_rn union all
    select 5 as num_rn union all
    select 6 as num_rn union all
    select 7 as num_rn union all
    select 8 as num_rn union all
    select 9 as num_rn
) t2
    ON t2.num_rn <  ((LENGTH(t1.image_file) - LENGTH(REPLACE(t1.image_file, @fild, '')))/length(@fild) + 1)
order by t2.num_rn
;