CREATE TABLE track(
 trackid INTEGER,trackname TEXT,trackartist INTEGER,FOREIGN KEY(trackartist) REFERENCES artist(artistid)

NSString* dbPath = [(NSArray*)NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]; dbPath = [dbPath stringByAppendingPathComponent:@"test.db"]; db = [FMDatabase databaseWithPath:dbPath]; if ([db open]) { NSLog(@"Database %@ opened", dbPath); //check for foreign_key NSString* sql = @"PRAGMA foreign_keys"; FMResultSet *rs = [db executeQuery:sql]; int enabled; if ([rs next]) {  enabled = [rs intForColumnIndex:0]; } [rs close]; if (!enabled) { // enable foreign_key  sql = @"PRAGMA foreign_keys = ON;"; [db executeUpdate:sql]; // check if successful  sql = @"PRAGMA foreign_keys"; FMResultSet *rs = [db executeQuery:sql]; if ([rs next]) {  enabled = [rs intForColumnIndex:0]; } [rs close]; } // do your stuff here,or just cache the connection } else { NSLog(@"Failed to open %@", dbPath); 

table1 is the parent table having id1 as primary key.  CREATE TABLE "table1" ("id1" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL)  table2 is the child table having id2 as a foreign key with reference to id1 of table1. CREATE TABLE table2 (  id2 INTEGER,  parent_id INTEGER,  description TEXT,  FOREIGN KEY (id2) REFERENCES table1(id1) 

Foreign keys are disabled by default. You have to enable them separately for each connection. The setting isn't "sticky". You have to do this every time you connect to a sqlite database. PRAGMA foreign_keys = ON;