.
, , , .
:
- ;
- ;
- ;
- .
. SQL- DELETE. , , . SQL- :
DELETE K.*, .
FR
WHERE ((.) = ));
SQL- , , .
. SQL- UPDA. , - .
, - :
UPDA
SET . =
WHERE ((Copy.Cayc) = Coece);
. . () () . , , . .
SQL- INSERT INTO, :
INSER INTO
SELECTC.*
FR
WHERE ((.)=-405);
. SQL- SELECT...INTO. () , , ( ). SQL- :
|
|
SELECT *
INTO
FROM
WHERE((.)=BETWEEN#1/01/98#AND#1/02/98#;
DDL SQL-, / . .
:
- ;
- ;
- ;
- .
SQL- CREA TABLE , (CHARACTER, INTEGER, DATETIME ..), CONSTRAINT , UNIQUE, ( ) , PRIMARYKEY, .
, , , , , , .*
* SQL SQL .
CREA TABLE C
( TEXT, TEXT, DATETIME,
CONSTRAINT C UNIQUE (, , ) PRIMARY KEY);
SQL- ALTER TABLE ADD COLUMN ( ) ADD CONSTRAINT( ). DROP COLUMN . , , - . FOREIGN KEY REFERENCES.
, , , _ :
ALTER TABLE ADD COLUMN CURRENCY;
ALTER TABLE Co DD CONSTRAINT OCo ;
ALTER TABLE DROPCOLUMNO;
ALTER TABLE ADD CONSTRAINT FOREIGN KEY(_)
REFERENCES (_);
ALTER TABLE DROP CONSTRAINT;
SQL- DROP TABLE . :
DROPTABLE ;
DROPINDEX ON ;
SQL- CREAINDEX UNIQUE WITH DISALLOW NULL IGNORE NULL / () . PRIMARY ( , .. ).
|
|
_ :
CREA UNIQUE INDEX
ON (_)
WITH DISALLOW NULL;
(VIEW) - . - , . , , .
, , - . - , . : - . - . DML , . - , ( , , ), . - , , . .
CREATE VIEW. CREATE VIEW ( ), , AS (), , :
CREATE VIEW Londonstaff
AS SELECT *
FROM Salespeople
WHERE city = 'London';
:
DROP VIEW < view name >