SQL DML

DEMO

CREATE TABLE T (
    TID INTEGER PRIMARY KEY AUTOINCREMENT,
    W   INTEGER,
    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
• ?????????