this code is not run on my mac, why sqlite do not open the database?

static sqlite3 *database;
static sqlite3_stmt *enableForeignKey;

@implementation DBAdapter

+ (sqlite3 *)sharedInstance {

    if (database == NULL) {
        sqlite3 *newDBconnection;

        NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        NSString *documentsDirectory = [paths objectAtIndex:0];
        NSString *path = [documentsDirectory stringByAppendingPathComponent:@"klb_db.sqlite"];

        if (sqlite3_open([path UTF8String], &newDBconnection) == SQLITE_OK) {   
            //NSLog(@"Database Successfully Opened :)");
            database = newDBconnection;

            if (sqlite3_prepare_v2(database, "PRAGMA foreign_keys = ON", -1, &enableForeignKey, NULL) != SQLITE_OK) {
                NSLog(@"ERROR IN PRAGMA!");
            }

            sqlite3_finalize(enableForeignKey);

        } else {
            NSLog(@"Error in opening database :(");
            database = NULL;
        }
    }

    return database;
}