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Hey guys welcome back.

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In this video we're just going to review some of the changes that would have made since the last time

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when we're creating our ad edit form for our cars.

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Someone to start off with the money.

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Vehicle listing window where you read that that I did what I labeled as our refresh button.

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So this refresh button will just refresh the grid each time a change is made.

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So let us take it for a spin firstly let's start with the ad new car.

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So when adding a new car I added validation to the form to make sure that at least the make and the

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model our presence when I click save changes then I'm going to get this please ensure that you provide

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a make and a model.

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So if I'm going to add a new one and let's say I had a Suzuki and swift and then I click save changes

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I also put in try catch because then year is expecting a value so it can pass into integer.

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So when I click save changes then my my arrow comes up from my exception right.

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So then if I provide a change a year sorry and I say 2013 and while those are only three fields that

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are absolutely necessary for it to work and click save changes it put in another message box that's

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it.

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Insert operation completed refresh grid to see changes.

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Right.

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So we did disclose that we wanted to manage the user's experience between adding or modifying data in

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the car and getting back to the grid.

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So if the display in this message box and I think we'll keep the window will close but then I can click

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refresh and then it will display the new field.

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Right.

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And then if I try to edit without selecting so even though you may see it highlighted blue it's not

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really selected.

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So if I click edit car I get a nasty arrow.

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But then once again this is just a try catch catching that arrow.

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That would have been an exception showing me that you know the index was both offering and just basically

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saying that I didn't select anything from the grid control right but then my program does not stop executing.

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So I can always rectify that by just clicking.

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And let's start with the record that we just added When I click Suzuki Swift click edit car then it

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brings up edit vehicles so I made sure to modify the title that comes up.

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So let me go back to ad car.

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When I click a new car it's the same form but when the label changes and to the title in the window

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changes.

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So do any typical use it could have been two different windows.

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That's not really our business to worry about.

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So I'm just changing it so the user feels like it's the same window at all times although it is the

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same with the book to feel like it's a different window sorry.

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And then what happens is that a functionality slightly different also.

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So we're getting the load the data preloaded I can change the VIN and the license plate number and just

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put in some kind of number click save changes and then it is a bit operation completed.

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So it's a similar message i click Okay.

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Similar behavior.

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And then I refresh and then I get the brand new data no deleting is kind of tricky because you can't

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delete related data.

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Meaning if I select see Subaru which I do believe I have our entire record to represents where already.

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If I click delete that I'm going to get some arrows seeing that you know I have to see that exception

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for details when I checked all that arrow.

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It was really because I have our entire record on Subaru so enough to delete all the entire records

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for the Subaru in order to delete the Subaru and that's just referential integrity coming over from

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the database.

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So that's not necessarily a bad thing.

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So if you get that error that's really what's happening.

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But I just created Suzuki Swift someone to delete it because I know I have no no records associated

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with it.

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So then I delete it will Oh well it's actually giving me an error.

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I did not expect that.

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So let us see exactly what that error is because I really didn't expect that one someone to go over

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to my code Western in debug mode.

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Go to my click event and then I'm just going to select the point where it's supposed to actually remove

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the car and then we're going to try that operation again.

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So I click it jumps the break point where it retrieve the car successfully so it knows that it's getting

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this is looking Swift.

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All right.

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And then I can use if someone to step through singles to see if changes at which point to throw is the

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exception.

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And then if I look in the exception object it says look inside of the inner exception for more details

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or I see an exception for more details so I can look at that and then it seeing that I have a constraint

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that conflicts with my data base.

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So I definitely have to check that out to see if there is an error into a record with that property

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with a car.

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Sir with that record in the database.

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So there is no related record I just checked but what is happening is that it is enforcing some design

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constraints.

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So in the design of my car into a record or well in the design of this table four types of cars on the

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I.D. or on the relationship.

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Actually there would be this inserts an update deletion of data rule.

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Right.

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So basically I can set no action or cascade.

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So it had to set cascade for it to just say OK I will delete the danger to this over is that if it deletes

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the red card then it will delete all associated or all related records if it bleeds car with the I.D.

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one can ever rent a record that is associated with car with I.D. one would also get deleted which you

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may not necessarily want.

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So you have to gauge that experience with your application.

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However we do see that you know we can probably go by the delete form no and we fix it at a later date.

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But I just wanted to get across the fact that we could modify our application to do some crud against

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the vehicle listing we could create a single form that has multiple purposes and we can write some cool

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code in our code file to handle the experience that our users have.

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So after finishing up our money vehicle listing we'll probably want to turn our attention to finishing

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up their entire record where we create a view similar to this where we can view all of the rental records

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coming in from the database and be able to modify them when needed.