views - SQL update table via join? -

i have following database , wish update room table. table room lists room type either single, double or king, price price of each room per night , name in hotel name of hotel.

what need change double rooms king rooms in scotty hotel , increase price 10%.

i know how update price , type when in single table, seems here need join hotel , room on hno , update. nested query maybe?

create table hotel  (    hno char(4),    name varchar(20)   not null,    address varchar(50),    constraint pk_hotel primary key (hno) );  create table room  (    rno char(4),    hno char(4),    type char(6) not null,    price decimal (7,2),    constraint pk_room primary key (hno, rno),    constraint fk_room foreign key (hno)    references hotel (hno) );   create table guest  (    gno char(4),    name varchar(20) not null,    address varchar(50),    constraint pk_guest primary key (gno)  );  create table booking   (    hno char(4),    gno char(4),    datefrom date,    dateto date,    rno char(4),    constraint pk_booking primary key (hno, gno, datefrom),    constraint fk_booking foreign key (gno)    references guest (gno),    constraint fk_booking_room foreign key (hno, rno)    references room (hno, rno),    constraint fk_booking_hotel foreign key (hno)    references hotel (hno) ); 

i have 2 main questions:

1. is possible update table, requires join?

2. i want list guests via view. can create view contains hotel name , number of distinct guests have ever stayed in hotel?

first, idea select ensure search/filter criteria correct:

select   h.name,   r.rno,   r.type,   r.price    room r    inner join hotel h   on h.hno = r.hno    h.name = 'scotty hotel'   ,   r.type = 'double' ; 

if targets correct rows, have @ 'em update query using same filter criteria, follows.

hint, pays copy entire select query , edit form new update query. eg mysql, replace from update (and leave contents of original from clause form new update clause), leave where in place, , use contents of select list original query basis on form new set clause (immediately prior where clause).

this code mysql:

update room r     inner join hotel h   on h.hno = r.hno  set   r.type = 'king',   r.price = r.price * 1.1    h.name = 'scotty hotel'   ,   r.type = 'double' ; 

this code ms sql server:

update r  set   r.type = 'king',   r.price = r.price * 1.1    room r    inner join hotel h   on h.hno = r.hno    h.name = 'scotty hotel'   ,   r.type = 'double' ;