, , UPDATE, DELETE, . , , , Peel ( snum=1001):
UPDATE Customers
SET rating = 200
WHERE snum = 1001;
UPDATE
UPDATE. SET , . , . , Motika , :
UPDATE Salespeople
SET sname = 'Gibson', city = 'Boston', comm =.10
WHERE snum = 1004;
Gibson, Motika , , Motika snum.
, , , , SET. , "SET Salespeople.sname = Gibson" UPDATE, "SET sname = Gibson".
SET UPDATE, , , . VALUES INSERT, ; . , . :
UPDATE Salespeople
SET comm = comm * 2;
, SET, , - UPDATE. , , , , :
UPDATE Salespeople
SET comm = comm * 2
WHERE city = 'London';
(NULL)
SET . NULL , , - (, , IS NULL). , NULL, :
UPDATE customers
SET rating = NULL
WHERE city = 'London';
.
:
INSERT ;
DELETE ;
UPDATE .
|
|
UPDATE DELETE, , . , INSERT, INSERT. , INSERT, . .
, , . , NULL. , , UPDATE , INSERT .
, , . , , , DML, 16.
SQL
1. , , , :
city San Jose,
name Bianco,
comm NULL,
cnum 1100.
2. , Clemens .
3. , 100.
4. Serres . Motika.
(. A .)