LocalDataBase

Its is to SAVE and FETCH data from local database CoreData-> insert,update and delete, Add Two buttons and Tableview in mainstoryboard, Create IBAction for the buttons one is for insert and another is for delete,

Create the NsmutableArray to store and display values in tableview.

NSMutableArray *tableDataArray;

Add the below code to insert button

 UIAlertView *alert=[[UIAlertView alloc]initWithTitle:@"Core Data" message:nil delegate:self cancelButtonTitle:nil otherButtonTitles:@"Cancel",@"Save", nil];
    alert.alertViewStyle = UIAlertViewStyleLoginAndPasswordInput;
    [alert textFieldAtIndex:0].placeholder = @"Emp_Name";
    [alert textFieldAtIndex:1].placeholder = @"Emp_Id";
    [alert textFieldAtIndex:1].secureTextEntry=NO;
    alert.tag=111;
    [alert show];

Add Alertview Delegate method:-

-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    /****************** Insert Data **********************/
    if (alertView.tag==111) {
        if (buttonIndex==1) {
           emp_nameTextField = [alertView textFieldAtIndex:0];
            emp_IDTextField = [alertView textFieldAtIndex:1];
            [self insertDataIntoDataBaseWithName:emp_nameTextField.text WithCity:emp_IDTextField.text];
        }
    }
    if (alertView.tag==222) {
        if (buttonIndex==1) {
            emp_nameTextField = [alertView textFieldAtIndex:0];
            emp_IDTextField = [alertView textFieldAtIndex:1];
            [self updateDataInDataBase:emp_nameTextField.text WithCity:emp_IDTextField.text];
        }

}

}

tag - 111 is for insert and tag -222 is for update, Added the insert method:-

-(void)insertDataIntoDataBaseWithName:(NSString *)name WithCity:(NSString *)city
{
    AppDelegate *appDel=(AppDelegate *)[UIApplication sharedApplication].delegate;
    _managedObjectContext = [appDel managedObjectContext];
    NSManagedObject *newDevice = [NSEntityDescription insertNewObjectForEntityForName:@"Employee" inManagedObjectContext:_managedObjectContext];
    
    [newDevice setValue:emp_nameTextField.text forKey:@"emp_name"];
    [newDevice setValue:emp_IDTextField.text forKey:@"emp_id"];
    
    NSError *error = nil;
    if ([_managedObjectContext save:&error]) {
        NSLog(@"data saved");
        [tableDataArray addObject:newDevice];
        [_mTableView reloadData];
    }
    else{
        NSLog(@"Error occured while saving");
    }
}

once You added the data needs to fetch it to display in Tableview,for fetch data added the below code,call this method in viewdidload{}

-(void)FetchDataFromDataBase{
    [tableDataArray removeAllObjects];
    AppDelegate *appDel=(AppDelegate *)[UIApplication sharedApplication].delegate;
    _managedObjectContext=[appDel managedObjectContext];
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Employee"
                                              inManagedObjectContext:_managedObjectContext];
    [fetchRequest setEntity:entity];
    NSError *error = nil;
    NSArray  *fetchedObjects = [_managedObjectContext executeFetchRequest:fetchRequest error:&error];
    if (fetchedObjects == nil) {
        NSLog(@"no object");
    }
    else
    {
        for(NSManagedObject* currentObj in fetchedObjects) {
            [tableDataArray addObject:currentObj];
        }}
    [_mTableView reloadData];
}