MySQL 8.0

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CREATE TABLE test (
    saledate DATETIME,
    refno INT,
    refnoext VARCHAR(255),  -- ???
    orderno INT,
    hash CHAR(32)
);
SET @json:='
    {"SALEDATE":"2021-08-25 4:11:32", 
     "REFNO":"23456",
     "REFNOEXT":"", 
     "ORDERNO":"7",
     "HASH":"4aa30dc0d6f67293bee9cee168b90524"}
';
CREATE PROCEDURE parse_and_save_json_to_table (param JSON)
BEGIN
    SELECT CONCAT('INSERT INTO test SET ',
                  GROUP_CONCAT(columnname, 
                               '=''', 
                               JSON_UNQUOTE(JSON_EXTRACT(param, CONCAT('$.', columnname))),
                               '''')) query
    FROM JSON_TABLE(JSON_KEYS(param),
                    '$[*]' COLUMNS( columnname VARCHAR(64) PATH '$')) columns
    INTO @sql;
    PREPARE stmt FROM @sql;
    EXECUTE stmt;
    DROP PREPARE stmt;
END
CALL parse_and_save_json_to_table(@json);
SELECT * FROM test;


saledate
refno
refnoext
orderno
hash


2021-08-25 04:11:32
23456

7
4aa30dc0d6f67293bee9cee168b90524