Using SET operations, display a list of customers that are interested in a car (prospect table) of the different make and model which they already own. Allow for white space and case differences. 

SI database is to be used for the above question, I've attached it below

 

OPTIONS optioncode CHAR(4) optiondesc VARCHAR2(30) optioncost NUMBER(7,2) # optionlistprice NUMBER(7.2) custname custstreet PROSPECT custname VARCHAR2(20) NOT NULL carmake VARCHAR2(10) NOT NULL carmodel VARCHAR2(10) caryear CHAR(4) VARCHAR2(12) carcolour cartrim. VARCHAR2(16) optioncode CHAR2(4) |+ CUSTOMER custcity custprovince custpostal custhphone CHAR(13) custbphone CHAR(13) Specialty Imports E-R Diagram VARCHAR2(20) VARCHAR2(20) NOT NULL VARCHAR2(20) NOT NULL CHAR(2) CHAR(7) NOT NULL DEFAULT "ON" NOT NULL NOT NULL NOT NULL SERVINV servinvno CHAR(5) servdate DATE NOT NULL custname VARCHAR2(20) NOT NULL carserial CHAR(8) NOT NULL partscost NUMBER(7,2) laborcost NUMBER(7,2) taxrate NUMBER(4.2) DEFAULT 13.0 SERVWORK servinvno CHAR(5) workdesc VARCHAR2(80) ||| Ho BASEOPTION ++ PURCHINV purchinvno CHAR(6) purchfrom VARCHAR2(15) purchdate DATE optioncode CHAR(4) carserial CHAR(8) carserial CHAR(8) custname VARCHAR2(20) carmake VARCHAR2(10) NOT NULL carmodel VARCHAR2(10) NOT NULL NOT NULL caryear extcolour VARCHAR2(12) NOT NULL H cartrim VARCHAR2(16) NOT NULL enginetype VARCHAR2(10) NOT NULL enginetype VARCHAR2(10) NOT NULL purchinvno CHAR(6) purchcost NUMBER(9.2) freightcost NUMBER(9.2) carlistprice NUMBER(9.2) CAR CHAR(4) Text TRADEINV saleinvno CHAR(6) carserial CHAR(8) tradeallow NUMBER(9,2) INVOPTION saleinvno CHAR(6) -ooptioncode CHAR(4) optionprice NUMBER(7,2) SALEINV saleinvno CHAR(6) saledate DATE NOT NULL salesman VARCHAR2(20) NOT NULL custname VARCHAR2(20) NOT NULL carserial insfire NOT NULL CHAR(8) CHAR(1) CHAR(1) inscollision insliability insproperty CHAR(1) CHAR(1) taxrate licfee discount NUMBER(8,2) commission NUMBER(8,2) carsaleprice NUMBER(9,2) NUMBER(4,2) DEFAULT 13.0 NUMBER(6,2) empname startdate title EMPLOYEE VARCHAR2(20) Ho DATE NOT NULL commissionrate NUMBER(3.1) VARCHAR2(26) manager VARCHAR2(20)