Streaming Table kafka parsing, parsing json string

[a773807...@gmail.com]

hi:
    how to parsing extension field to extension_channel, extension_message ?
    my extension field is string but is json

    大家好，请问kylin中怎么解析我下面的json中，extenson字段，能吧extension拆开解析么？

{
    "ip_risk_level":"0",
    "assocAcctType":255,
    "phone_risk_level":"0",
    "risk_level":0,
    "antisdk_risk_level":0,
    "@timestamp":"XXX",
    "antisdk_time_stamp":"XXX",
    "phone":"XXX",
    "uid":"XXX",
    "mapping_rule_name":"",
    "appId":"XXX",
    "ip_country_code":"XXX",
    "antisdk_pcid":"XXX",
    "antisdk_duokai_num":"1",
    "timestamp":1586786095164,
    "assocAcctId":"",
    "device":"XXX",
    "antisdk_ip":"XXX",
    "ip_risk_mask":"0",
    "ip":"XXX",
    "antisdk_intercept_reason":"0",
    "antisdk_mask":"0",
    "tags":[
        "result"
    ],
    "mapping_rule_id":"",
    "mapping_rule_score":"0",
    
"extension":"{"channel":"XXX","message":"?","sex":0,"target_uid":XXX,"version":"XXX"}",
    "termType":2,
    "host":"XXX"
}



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