SQL DDL und DML
DEMO
CREATE TABLE T (
TID INTEGER PRIMARY KEY AUTOINCREMENT,
W TEXT,
R REAL,
B BLOB,
UID INTEGER,
D INTEGER CHECK ( D >= 19000101),
DIM INTEGER CHECK ( DIM >= 0),
K INTEGER CHECK ( K >= 0 AND K <= 100 ∗ DIM ),
FOREIGN KEY ( W ) REFERENCES B ( BID ) ON DELETE CASCADE ,
FOREIGN KEY ( UID ) REFERENCES U ( UID ) ON DELETE RESTRICT
);
ALTER TABLE T
ADD TR INTEGER DEFAULT NULL REFERENCES B ( BID ) ON DELETE SET NULL;
INSERT INTO Training (Wer, UebungsID, Datum, VALUES
("3", "103" ,"20240326", "60", "100"),
("1", "102" ,"20240326", "60", "350");
ON DELETE
- CASCADE
- RESTRICT
-
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