00:01So for those that just joined us, I'm Larry Young with the editor team, and I have with me Jennifer Cadkin from the…

00:05…editor team, and we're going to talk about in the next 20 minutes, real quickly, is finding and fixing errors using…

00:11…topologies. So this is with the existing software. What you can do right now with 10 and 9.x and so on.

00:19So just real quickly, what are topologies all about? Well topologies are about managing your spatial integrity.

00:25There are two types of topologies—there are geodatabase topologies, which is persisted, lives in the geodatabase…

00:33…and then there's also the things called map topologies, which you create on the fly within ArcMap.

00:40Both of them allow you to edit coincident geometries, move things together. That's one reason why you use a topology.

00:47The other reason you might use a topology is you want to create rules and have these rules checked to see if you are…

00:54…violating them. So you might have polygons that overlap.

00:57You might have streets that need to intersect that actually don't, and you need a geodatabase topology in order to check these rules.

01:05Okay, so those are the two main things that people are normally looking for with topologies is moving geometries…

01:10…together and being able to define and check against the rules.

01:15So what are some of these rules that you can define? Well you can define rules on a feature class.

01:20You can also define them against specific subtypes within your feature class.

01:26Once you define these rules and you've built your topology, you can then validate that topology…

01:31…and we'll check to see if your data has violated any of these rules that you've defined, and again these rules are things…

01:37…like Polygons can't overlap. Roads can't intersect, or if roads do intersect, you need to have a…

01:44…they need to be broken at that point of intersection and so on, and these rules can be saved.

01:50You can pass rules around between different datasets by saving them out to rule files and loading them into other datasets.

01:58As I mentioned here are some of the examples of the type of rules that you might want to apply.

02:04So when you do apply, when you do set up these rules and you do validate your data against this set of rules you define…

02:11…you may get some errors. Once you get these errors, there are different things that you can do about them.

02:17You can try to fix those errors. You can mark those as exceptions.

02:22There are some built-in fixes for those errors that you can try to apply, and JJ's, or Jennifer's going to show you all those…

02:31…things that you can do about fixing and managing these errors that you might create.

02:37So again that's just a quick overview, and we're going to just jump right in again to the demos and start showing you how can…

02:43…how you can validate, find these errors, and start to fix them.

02:50Okay, so I'm going to show you how to find and review and fix some topology errors.

02:57I'm going to first show you a parcel dataset for Manatee County in Florida, and then we'll look at a roads and highway dataset.

03:05First let's look at the topology and see, get some more information about what this topology is.

03:12It's a pretty, it doesn't have a lot of rules, but it does include some Must not overlap rules and…

03:17…Boundary must be covered, so the parcels must be covered by parcel lines.

03:22The parcel line must not have dangles and that sort of thing. So let's turn on our topology.

03:29We can see there's quite a number of errors.

03:32We're going to zoom in on an area that has a number of errors that we want to review.

03:37So we need to start an edit session, and I have multiple workspaces so I had to let it know which workspace I wanted to edit.

03:47I don't need the Create Features window because I won't be creating features, but I do need the Error Inspector window, and in…

03:54…the Error Inspector window, I can search the rules that are in the area so that I can interrogate them…

04:01…so as I click in the error inspector you can see that the feature, or the error becomes highlighted, and I can also see…

04:11…just a variety of errors that are in this area. So in this area there's Boundary must be covered by. There's also a Must not overlap.

04:20If I see an area of interest and I want to know what rules are being violated in that area, I can use the Fix Topology Error tool.

04:29And I can interact with the map and select those errors, and once those errors are in the Error Inspector, there's a…

04:35…context menu available to me that I can use to work with the features.

04:41So in this area, I can see that my parcels are not covered by…

04:46…my parcel line, so they're violating that rule, and I can use the context menu to real quickly create my parcel line features.

04:56When I do that, it creates a dirty area where the edit is made, and I can see that dirty area here and after doing that I can…

05:05…validate those edits and make sure that I, that no additional errors were introduced or that I cleaned up the …

05:12…errors I meant to. So let's zoom back out and look at a different error now.

05:18This area, there's three errors and I'm going to use the Fix Topology Error tool to figure out what those are, and I see another…

05:28…Boundary must be covered by error and a couple Must not have dangles.

05:34So if I turn off the topology you might be able to see that there actually are parcel lines in that area, and in this case there's a…

05:44…slight offset between the parcel line and the parcel, so I'm going to reshape the parcel line to align with the parcel boundary.

05:53So I am going to select the feature, and I've also selected the parcel so I want to make sure not to edit that so I'm going to…

06:03…use the selection chip to select the parcel line and then use the Reshape Feature tool and turn off the parcel line so that I…

06:12…ensure that I snapped to parcels, and then I can trace along that parcel boundary and reshape the feature.

06:21And once again I've created a dirty area that I want to validate, and you can see that the Boundary must be covered by rule…

06:29…violation has been cleared up, and now I want to work on these Must not have dangles errors, and I'm going to use the…

06:36…context menu to trim these because I want to trim them so that they snap to the parcel or the parcel line and parcel intersection.

06:47So I'm going to enter in a value (inaudible). Don't know why that…that's interesting.

07:07So I'm not sure why maybe my…(inaudible) maybe I forgot my number that I'm supposed to enter.

07:25Well anyway, it should trim it. It should eliminate the dangle.

07:28It should split that parcel line at the intersection point and the end points should align, and I'm going to zoom back out to that…

07:38…further out extent, and I'm going to look at a different rule.

07:41I'm going to look at the Subdivision must not overlap error, and you can see that there's a number of Subdivision must not…

07:49…overlap errors that are caused by this feature 46816 that has a slight offset so it caused a lot of overlap.

07:58So now I want to clean up some of that overlap in this particular area, and I can do a search now, and for each of these there's…

08:08…a context menu that I can use, and in this case I want to merge the area overlap onto the smaller subdivision feature…

08:16…so I can use the context menu there, real quickly eliminate that overlap.

08:26Once again I need to validate the topology, and now that I've done that you can see there's some gaps in this data that…

08:34…I can now work on to make the data coincidence, and in this case I'm going to drag some vertices around, and then I can…

08:43…also reshape the feature on this side so that they align, and for this particular data, we don't have a Must not have gaps…

08:58…because the subdivision and the parcels and the lots, they don't form a continuous surface.

09:03There's intentional breaks where the streets and things go through, which is why these gaps didn't get picked up, but we…

09:12…were able to still see them clearly and resolve them.

09:16So now I'm going to look at the, we're going to look at the roads and highways dataset, and this is also a county…

09:24…and you can see that the centerlines are all ending along the county boundary, and these are okay.

09:30We, these aren't real errors, well they're errors, but they're errors that we've excepted and that we're going to mark as…

09:36…exceptions so they'll stay in the geodatabase, but they'll just be flagged differently.

09:42So what I want to do is along the county boundary is select a number of these errors that are at the county boundary and…

09:53…I can mark them as exception and it clears them off of the map.

09:57At any time I can go back and I can review those point exceptions, and if I want to I can return them to an error status.

10:06But now what I'm going to do is I'm going to look at this dirty area, and what's going on in here is that we've heads up…

10:13…digitized some new roads as well as added an intersection point based on x,y and we want to see if these edits have…

10:22…cleaned up our topology, and in this case we still have some errors that we want to look at.

10:29So let's look at these two. This one on the east end is a Must not have dangle, and we know that that is an error because…

10:38…we don't have data here yet, and without the basemap it's harder to see, but the network is too slow right now.

10:46So let's zoom in and look at this particular one. And to learn more about a particular rule and what the fix may be…

10:54…you can review the rule description, and in this case we need to have an intersection point where the two streets…

11:02…come together, and so what I'm going to do here is I'm going to select the feature and I'm going to use the edit tools to…

11:10…drag it and snap it to that end point, and when I validate you see that that rule gets cleared up, and now to look at the other rule.

11:23This rule is caused because, sorry, this error is a…the Centerlines can only meet at an end point, and in this case I'm going to…

11:40…select the features, and what you can see here is that there's two features that come together, and what we really need is…

11:49…the northernmost line to be split at the intersection points.

11:52So I can use the context menu to split them, and now you can see that I have three features and that the rule has been…

12:01…cleared up, and so that was a quick run-through of how to find topology errors…

12:09…and to fix them using the context menu as well as the editor toolbar.

12:18Alright, thanks Jennifer. So just to, a quick summary then of what we're looking at.

12:24So in order to create rules, you need to have a geodatabase topology, and you can create rules.

12:30You can validate your topology against these rules and it'll discover errors that you have in your data and then you can…

12:37…then use existing tools to clean up those errors, and there's a couple of different ways you can go about it.

12:43You can use predefined fixes that we have in there where you right-click on the error as Jennifer showed, and you…

12:49…can see some available fixes, and that's the best way to go if it will fix the issue, but sometimes you can go a little…

12:56…a little too far with those fixes. So those automated fixes are not meant to be a cure-all and fix all the problems.

13:04So there are times when you still need to go to the actual editor tools and clean things up as you go.

13:10Another point, another bullet I should probably have on here is that you also had to be careful in your defining your rules and not define…

13:17…too many rules, or define rules that you know you're going to have a whole bunch of violations of.

13:24For instance, the polygon parcels, as an example, Parcels cannot have gaps.

13:30We have people define that sort of rule, and obviously you get gaps everywhere.

13:34You have right-of-ways and that type of thing.

13:36So unless you're maintaining right-of-ways and you have a complete continuous parcel layer, don't define a rule like that...

13:42…because you'll just get so many violations it'll be too difficult to clean them all up. So that's just some of the ground rules.

13:49Again, if you want to know more about topologies, it's a good session.

13:52The bottom one there on Thursday morning on understanding topologies and the geodatabase.

13:57It'll go through the whole process of creating topologies and so on, and then again, there are some of the other editor…

14:04…sessions that we have during the week, and of course, you can always come down to the island if you have any more…

14:09…issues or questions about topologies. So, any questions on what we covered in the last fifteen, sixteen minutes?

14:17Yup. Can you hear? I'm sorry I couldn't hear you.

14:28The question, Are these in 10.0 and 9.3? These are started in 8.3, so 8.3 all the way up to 10, you're good to go.