MySQL 8.0

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CREATE TABLE tab( jsdata JSON );
INSERT INTO tab VALUES('[ { "price": "1000", "itemcode": "1", "itemname": "Break Pads", "quantity": "1" }, { "price": "800", "itemcode": "3", "itemname": "Break Oil", "quantity": "1" } ]');
SELECT t.* 
  FROM tab
 CROSS JOIN
     JSON_TABLE(jsdata, '$[*]' COLUMNS (
                price    VARCHAR(100) PATH '$.price',
                itemcode VARCHAR(100) PATH '$.itemcode',
                itemname VARCHAR(100) PATH '$.itemname',
                quantity VARCHAR(100) PATH '$.quantity')
     ) t
     


price
itemcode
itemname
quantity


1000
1
Break Pads
1

800
3
Break Oil
1


SELECT JSON_UNQUOTE(JSON_EXTRACT(jsdata, CONCAT('$[',@rn+1,'].price'))) AS price,
       JSON_UNQUOTE(JSON_EXTRACT(jsdata, CONCAT('$[',@rn+1,'].itemcode'))) AS itemcode,
       JSON_UNQUOTE(JSON_EXTRACT(jsdata, CONCAT('$[',@rn+1,'].itemname'))) AS itemname,
       JSON_UNQUOTE(JSON_EXTRACT(jsdata, CONCAT('$[',@rn+1,'].quantity'))) AS quantity,
       @rn :=  @rn + 1 as rn
  FROM tab
 CROSS JOIN (SELECT @rn := -1
               FROM information_schema.tables) AS iter 
 WHERE @rn < JSON_LENGTH(JSON_EXTRACT(jsdata, '$[*]')) - 1             


price
itemcode
itemname
quantity
rn


1000
1
Break Pads
1
0

800
3
Break Oil
1
1