DELETE 
FROM
    ITEM AS I 
WHERE
    NOT EXISTS ( 
        SELECT
              1 
        FROM
            STOCK S 
        WHERE
            I.ITEM_CODE = S.ITEM_CODE
    ); 

DELETE 
FROM
    ITEM AS I 
WHERE
    EXISTS ( 
        SELECT
              1 
        FROM
            STOCK S 
        WHERE
            I.ITEM_CODE = S.ITEM_CODE
            AND S.LAST_DELIVERY_DATE <= DATE ('2023-06-01', '-6 months') 
            AND S.ACTUAL_AMT = 0 
            AND I.STOCK_MANAGEMENT_TYPE = 1
    )
;