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Come utilizzare una chiave esterna in sqlite?

Come selvin ha suggerito l'uso su delete cascade

http://www.sqlite.org/foreignkeys.html

Tabella1

CREATE TABLE table1 (
  id PRIMARY KEY  
 ,entry1 text,entry2 text
);

Allora

insert into table1 values(1,"aaaa","aaaaa");
insert into table1 values(2,"bbbb","bbbbb");

Tabella2

CREATE TABLE table2(
  id int references table1(id) ON DELETE CASCADE, entryx text, constant text
);


insert into table2 values(1,"aaaa","aaaaa");
insert into table2 values(1," baaaa ","baaaaaaa");
insert into table2 values(1,"  caaaa ","caaaaaaa")
insert into table2 values(2,"bbbb","bbbbb"); 

Tabelle dopo l'ingresso

sqlite> select * from table1;
id          entry1      entry2    
----------  ----------  ----------
1           aaaa        aaaaa     
2           bbbb        bbbbb     
sqlite> select * from table2;
id          entryx      constant  
----------  ----------  ----------
1           aaaa        aaaaa      
1           baaaa       baaaaaaa  
1           caaaa       caaaaaaa  
2           bbbb        bbbbb  

Elimina

sqlite> delete from table1 where id=1;

Tabelle dopo l'eliminazione

sqlite> select * from table2;
id          entryx      constant  
----------  ----------  ----------
2           bbbb        bbbbb     


sqlite> select * from table1;
id          entry1      entry2    
----------  ----------  ----------
2           bbbb        bbbbb