-- Place your SQL code here
DELETE FROM vn.claimLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.itemLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.entryLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.supplierLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.zoneLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.travelLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.routeLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 
DELETE FROM vn.clientLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL;
DELETE FROM vn.shelvingLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL;
DELETE FROM vn.ticketLog
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL;
DELETE FROM vn.workerLog  
    WHERE oldInstance IS NULL
        AND newInstance IS NULL
        AND `description` IS NULL; 