SQL Server 2019

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WITH TABLE_ORIGEN AS
(

SELECT '{ "RESPONSECODE": "OK", "DICTAMEN":	"MALO", "REGLAS": {"R20000A":0,"R20000B":0,"R20000C":2,"R20101A":19,"R20101B":19,"R20201A":19,"R20201B":19,"R20102":"DOMINICANA","R20202":"4","R20103":1,"R20203":0,"R20104":0,"R20204":0,"R20105A":0,"R20105B":0,"R20205A":0,"R20205B":0,"R20106A":0,"R20106B":0,"R20106C":0,"R20206A":0,"R20206B":0,"R20206C":0,"R20107A":0,"R20107B":0,"R20107C":0,"R20207A":0,"R20207B":0,"R20207C":0,"R20108A":0,"R20108B":0,"R20208A":0,"R20208B":0,"R20109A":true,"R20109B":true,"R20109C":true,"R20109D":true,"R20209A":true,"R20209B":true,"R20209C":true,"R20209D":true,"R30100":1000}}' AS respuesta_api
  UNION
  SELECT '{ "RESPONSECODE": "OK", "DICTAMEN":	"APROBADO", "REGLAS": {"R10001":0,"R10002":1,"R10003":0,"R10004":0}}' AS respuesta_api
) 
SELECT JSON_VALUE(respuesta_api, '$.RESPONSECODE') AS RESPONSECODE ,
    JSON_VALUE(respuesta_api, '$.DICTAMEN') AS DICTAMEN ,
    JSON_VALUE(respuesta_api, '$.REGLAS.R20000A') AS R20000A,
    JSON_VALUE(respuesta_api, '$.REGLAS.R20000B') AS R20000B,
    JSON_VALUE(respuesta_api, '$.REGLAS.R20000C') AS R20000C,
    JSON_VALUE(respuesta_api, '$.REGLAS.R20101A') AS R20101A,
    JSON_VALUE(respuesta_api, '$.REGLAS.R10001') AS R10001
    -- Following JSON properties in `REGLAS`
from TABLE_ORIGEN

RESPONSECODE	DICTAMEN	R20000A	R20000B	R20000C	R20101A	R10001
OK	MALO	0	0	2	19	null
OK	APROBADO	null	null	null	null	0

WITH TABLE_ORIGEN AS
(

SELECT '{ "RESPONSECODE": "OK", "DICTAMEN":	"MALO", "REGLAS": {"R20000A":0,"R20000B":0,"R20000C":2,"R20101A":19,"R20101B":19,"R20201A":19,"R20201B":19,"R20102":"DOMINICANA","R20202":"4","R20103":1,"R20203":0,"R20104":0,"R20204":0,"R20105A":0,"R20105B":0,"R20205A":0,"R20205B":0,"R20106A":0,"R20106B":0,"R20106C":0,"R20206A":0,"R20206B":0,"R20206C":0,"R20107A":0,"R20107B":0,"R20107C":0,"R20207A":0,"R20207B":0,"R20207C":0,"R20108A":0,"R20108B":0,"R20208A":0,"R20208B":0,"R20109A":true,"R20109B":true,"R20109C":true,"R20109D":true,"R20209A":true,"R20209B":true,"R20209C":true,"R20209D":true,"R30100":1000}}' AS respuesta_api
  UNION
  SELECT '{ "RESPONSECODE": "OK", "DICTAMEN":	"APROBADO", "REGLAS": {"R10001":0,"R10002":1,"R10003":0,"R10004":0}}' AS respuesta_api
) 
SELECT JSON_VALUE(respuesta_api, '$.RESPONSECODE') AS RESPONSECODE ,
    JSON_VALUE(respuesta_api, '$.DICTAMEN') AS DICTAMEN ,
    JSON_VALUE(respuesta_api, '$.REGLAS.R10001') AS R10001,
    JSON_VALUE(JSON_QUERY(respuesta_api, '$.REGLAS'), '$.R20000A') AS R20000A,
    JSON_VALUE(JSON_QUERY(respuesta_api, '$.REGLAS'), '$.R20000B') AS R20000B,
    JSON_VALUE(JSON_QUERY(respuesta_api, '$.REGLAS'), '$.R20000C') AS R20000C,
    JSON_VALUE(JSON_QUERY(respuesta_api, '$.REGLAS'), '$.R20101A') AS R20101A,
    JSON_VALUE(JSON_QUERY(respuesta_api, '$.REGLAS'), '$.R10001') AS R10001
    -- Following JSON properties in `REGLAS`
from TABLE_ORIGEN

RESPONSECODE	DICTAMEN	R10001	R20000A	R20000B	R20000C	R20101A	R10001
OK	MALO	null	0	0	2	19	null
OK	APROBADO	0	null	null	null	null	0