ON DELETE CASCADE not working in c#

Question

When I delete a primary key with ExecuteNonQuery() in C# from the first table it doesn't affect the second table. But when I do the same with SQLiteStudio it does affect the second table.

Here is my SQLite code:

CREATE TABLE Zdravila(
   ID INTEGER PRIMARY KEY,
   NACIONALNA_SIFRA INTEGER UNIQUE NOT NULL,
   IME_ZDRAVILA TEXT,
   POIMENOVANJE_IZDELKA TEXT NOT NULL,
   SIFRA_REZIM_IZDAJE INTEGER NOT NULL,
   ATC_OZNAKA TEXT   NOT NULL,
   NAZIV_POTI_UPORABE TEXT NOT NULL,
   FOREIGN KEY(NACIONALNA_SIFRA) REFERENCES LastnostiZdravila(NACIONALNA_SIFRA) ON DELETE CASCADE ON UPDATE CASCADE
   );

CREATE TABLE LastnostiZdravila(
   NACIONALNA_SIFRA INTEGER PRIMARY KEY,
   NAZIV_FARMACEVTSKE_OBLIKE  TEXT NOT NULL,
   KOLICINA_OSNOVNE_ENOTE  INTEGER NOT NULL CHECK (KOLICINA_OSNOVNE_ENOTE > 0),
   OZNAKA_OSNOVNE_ENOTE    TEXT NOT NULL,
   PAKIRANJE   TEXT NOT NULL,
   SIFRA_IMETNIKA_DOVOLJENJA  TEXT NOT NULL
   );

PRAGMA foreign_keys = ON;

And my C# code:

SQLiteConnection conn = new SQLiteConnection(poveziZBazo);
                SQLiteCommand sqlQuery = new SQLiteCommand(sql);
                sqlQuery.Connection = conn;
                conn.Open();
                SQLiteTransaction trans;
                trans = conn.BeginTransaction();

                sqlQuery.CommandText = sql;
                j = sqlQuery.ExecuteNonQuery();
                trans.Commit();
                sqlQuery.Dispose();
                conn.Close();

And my Query: "DELETE FROM LastnostiZdravila WHERE NACIONALNA_SIFRA = " + "'" + NacionalnaSifraBrisanje + "'" + ";";

(I check NacionalnaSifraBrisanje for sql commands)

Answer 1

According to http://sqlite.org/pragma.html#pragma_foreign_keys:

As of SQLite version 3.6.19, the default setting for foreign key enforcement is OFF. However, that might change in a future release of SQLite.

As for now, this still defaults to false.

CL already told you that foreign_keys setting is "per connection" - what it means is that every time you make a new connection to the SQLite database, the foreign_keys pragma is set to default value, which is false.

What you need to do is to execute PRAGMA foreign_keys = 1; after every connection you make to the SQLite, so foreign keys are honored by your C# application.

This is actually what SQLiteStudio does internally and that's why it works there.