Update value core data - iphone

Question

I need to update the value of the desired cell in my core data. I have a cell (ID) with a known value to me. I need to find the value and replace. I know how to change the elements of the array. The following shows how I do it. But I have to change the field (ID) in MyBase. value that I need to change will be equal to fromIndexPath.row. The value on which I need to change toIndexPath.row.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath
*)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath {
if (fromIndexPath.section == toIndexPath.section) {
NSFetchRequest* fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription* entityDescription = [NSEntityDescription entityForName:#"MyBase"
inManagedObjectContext:self.objectContext];
[fetchRequest setEntity:entityDescription];
empArray = [(NSArray*)[self.objectContext executeFetchRequest:fetchRequest error:nil] mutableCopy];
MyBase *employee = [empArray objectAtIndex:fromIndexPath.row];
[empArray removeObjectAtIndex:fromIndexPath.row];
[empArray insertObject:objectToMove atIndex:toIndexPath.row];
}
}

Answer 1

for update core data, you can try this:
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:#:#"Employee"
inManagedObjectContext:self.managedObjectContext];
[request setEntity:entity];
NSPredicate *pred = [NSPredicate predicateWithFormat:[NSString stringWithFormat:#"empId = %d", 12345]];
[request setPredicate:pred];
NSArray *empArray=[self.managedObjectContext executeFetchRequest:request error:nil];
[request release];
if ([empArray count] > 0){
Employee *employee = [empArray objectAtIndex:fromIndexPath.row];;
employee.empSalary=[NSNumber numberWithInt:45000];
employee.empName=#"John";
employee.empDesignation=#"Analysist";
employee.empExp=#"4 Years";
[self.managedObjectContext save:nil];