Oracle 18c

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CREATE TABLE test (id INT, jsondata VARCHAR2(1000));
INSERT INTO test VALUES
(345,  '[{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"100"},{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"900"}]');
1 rows affected

INSERT INTO test VALUES
(234,  '[]');
1 rows affected

INSERT INTO test VALUES
(235,  '[{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"100"}]');
1 rows affected

SELECT * FROM test;


ID
JSONDATA


345
[{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"100"},{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"900"}]

234
[]

235
[{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"100"}]


SELECT test.id, 
       JSON_VALUE(test.jsondata, '$[0].items[0]._id') item1_id, 
       JSON_VALUE(test.jsondata, '$[0].items[0].type_id') item1_type_id, 
       JSON_VALUE(test.jsondata, '$[0].items[1]._id') item2_id, 
       JSON_VALUE(test.jsondata, '$[0].items[1].type_id') item2_type_id, 
       JSON_VALUE(test.jsondata, '$[0].contr') contr
FROM test


ID
ITEM1_ID
ITEM1_TYPE_ID
ITEM2_ID
ITEM2_TYPE_ID
CONTR


345
3435
908
null
null
100

234
null
null
null
null
null

235
3435
908
null
null
100


SELECT test.id,
       jsontable.*
FROM test
CROSS JOIN JSON_TABLE(test.jsondata,
                      '$[*]' COLUMNS ( row_number FOR ORDINALITY,
                                       id INT PATH '$.items[0]._id',
                                       type_id INT PATH '$.items[0].type_id',
                                       contr VARCHAR2(10) PATH '$.contr' )) jsontable


ID
ROW_NUMBER
ID
TYPE_ID
CONTR


345
1
3435
908
100

345
2
3435
908
900

235
1
3435
908
100

ID	JSONDATA
345	[{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"100"},{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"900"}]
234	[]
235	[{"items":[{"type":"item","_id":3435,"type_id":0908,"are":""}],"contr":"100"}]

ID	ITEM1_ID	ITEM1_TYPE_ID	ITEM2_ID	ITEM2_TYPE_ID	CONTR
345	3435	908	null	null	100
234	null	null	null	null	null
235	3435	908	null	null	100