iOS - Insert ไม่เข้าอะครับ คือกำลังงว่าเป็นที่อะไร ช่วยดูหน่อยครับ

- (IBAction)add_ol:(id)sender {
    
   
    sqlite3_stmt    *statement;
    const char *dbpath = [_databasePath UTF8String];
   
    if (sqlite3_open(dbpath, &_contactDB) == SQLITE_OK)
    {
        [_name_ol resignFirstResponder];
        [_tel_ol resignFirstResponder];
        
        
        
        NSString *insertSQL = [NSString stringWithFormat:@"INSERT INTO 'tb_tel' ('name_tel','number_tel') VALUES ('111tt','222rr')"];
        
        const char *insert_stmt = [insertSQL UTF8String];
        
        NSLog(@"%d",sqlite3_prepare_v2(_contactDB, insert_stmt,  -1, &statement, NULL));
        
       
        
        NSLog(@"%d",sqlite3_step(statement));
    }
    


}