Essential GIS Workflows: Exploring Geospatial Relationships

Name: Essential GIS Workflows: Exploring Geospatial Relationships
Author: Wade Wilson

Learn about geospatial relationships and how they are used in GIS software

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Course: On-Demand

Hello, my name is Wade Wilson, and in these lessons, we will learn exploring geospatial relationships. In this lesson, I'll be looking at tools for exploring geospatial data. So to start, first we'll look at what's called the identify. So in ArcGIS Pro software, you have this button here, which is an explore button, and typically if you click on a point, and in this case, we're going to identify everything that this point that we just clicked at intersects with all the data that's on. It's taken a while because we have all the different layers on here, and it's trying to find matches for anything that that point touches that falls through. So this is what's called a pop-up box. And so I clicked right here, and you can see this address point is East Hillsboro Avenue. Because there's a lot of different raster cells near that point, it identified all of those. That's this world imagery raster image, so if you click on these as you go down, you can see the shape link, shape area, and then this is the information about that square, and one of these actually identifies the color to be represented as the value in there. Those are the two datasets that we were able to identify on this map. Now it took a long time because it did go in and identify all these different cells. If you don't want to do that, you can come in here and you can say, I only want the top most layer, and it'll go a lot quicker. So if I close this box, I come back to the map, and I now click on that point. It's identifying just that address point. In this case, there are a lot of address points, so it's still taking a little bit of time. But when it comes back, you can see it's only the address point that was identified in this case, and we can see the attributes associated with that address point. That's one way to query and identify features on a map. One of the other more common ways is to come in here and just simply select, and there's several different ways to select. I typically just use a rectangle if it's going to meet my needs, so I can just draw a box around that point right there, and it's going in and it's selecting that point. And then if we open up the attribute table for that point, we can see that I selected one of those. If I want to see that feature, I can just say I only want to see the selected feature. And again, we can see it's 6305 East Hillsboro Avenue. I go back to my map, we can see it's highlighted. If I want to select a group query, a group of addresses, and this is helpful sometimes if you've got several in here and we're looking for a particular address, but we don't know which one. Let's zoom in a little bit closer. Since it's regenerated, I'll come in with my select by rectangle. You can see the rectangle there. I'll select all of these points, and as soon as it goes through the selection processes, we can go back to the table to take a look at the information associated with those points. In this case, it also selected the building polygon. So if I want to query and identify or learn information about those points, I go to the address point. And again, we still have it filtered to just show the selected records and we can see the address varies for each of those points. So there is not a single address for the building. They each individually have their own street number. So we can use this information to go in and look at a different way to query information. So let's see if we can select by attributes. So we don't know where a certain feature is, but we know something about that feature like the address. So in this case, we're going to do a query and we're going to look for 6203 East Hillsborough Avenue and we're going to select by attributes to do this. So first let me clear my selection. Let's go back to the map and we're going to go to select by attributes. That's the address point feature that we're searching. So we're going to go look in that table and we want a new selection and the expression is going to be this field full address. So we come over here change our field to full address is equal to 6213 East Hillsborough Avenue and then we apply and it's going through searching all the different features in there. You can see it's now selected. So if I open up the table, we can now see that it's selected that through a query. One feature I'll show you here with the Esri software is it auto completes. So if I'm typing in 6213, it goes ahead and tries to complete the entire field here, but it was a little easier here coming in just copying the value in there and pasted it in. Some other queries that might be more efficient to use the auto complete. In this case, it is not. So now let's look at select by location and this is a way we can do a query and we want to identify all the points that fall within this building footprint. So the first thing I need to do is I'm going to select the building footprint and so I select it by using my select tool, select by rectangle, I just drew a rectangle within the box there. Now I'm going to go select by location. The input features I want to select again is the address point features and I want the ones that intersect and my select and feature is coming from the building footprint and you can do a distance if you wish. In this case, we're going to just do a intersect. We are using zero feet. So this is basically anything that falls within the building footprint that intersects that footprint is going to be selected. If we wanted to go a little bit beyond that then we could put a search distance so that it wouldn't have to fall it totally within the building footprint for us to be able to select it. And again, it's going to be a new selection. So now hit apply and it's doing the query and this is again a select by location. So we're selecting one feature based on this location using another feature. Okay, and it's completed and you can see it is now selected all the address points that intersected the selected feature from the building polygon. Thanks for watching. Stay tuned for the next lesson where I will talk about tabular relationships.

Beginner Provider : Wade Wilson 4 Lessons · 26m in Arabic, German, English, Spanish, French, Portuguese, Chinese

Course Description

What does it mean to join a table? What is the difference between a joined and related table? Learning how to properly analyze data in GIS software is essential, which is why this course will demonstrate the tools and methods used to explore the relationship between spatial data and tabular data. The topics discussed in this course will provide a foundation for understanding how to analyze and manipulate data through spatial relationships, network analysis, and topology.

In this course on Essential GIS Workflows: Exploring Geospatial Relationships, the tools to query geospatial data using spatial relationships and database queries will be explained and demonstrated. Methods for analyzing spatial data will be explored by showing the tools and queries available for the spatial analysis of two data sets. By the end of this course, you will understand that spatial data provides many unique opportunities for data analysis that is not possible with tabular data sets.

What You'll Learn

Explore the tools and methods used to investigate relationships between spatial data and tabular data in GIS software
Understand what a relational database is and how it relates to tabular data
Perform proximity-based analysis to explore how data is related by distance
Join data by intersection or proximity, and distinguish a joined table from a related table
Query geospatial data using spatial relationships and database queries
Apply tools for analysis and data manipulation through spatial relationships, network analysis, and topology

Key Takeaways

Properly analyzing data in GIS software depends on understanding how spatial data relates to tabular data.
Spatial relationships, network analysis, and topology provide the foundation for analyzing and manipulating GIS data.
Geospatial data can be queried using both spatial relationships and database queries.
Spatial data offers unique opportunities for analysis that are not possible with tabular data sets alone.

Frequently Asked Questions

What does this course cover?

It demonstrates the tools and methods used to explore the relationship between spatial data and tabular data, covering spatial relationships, network analysis, and topology. It explains how to query geospatial data using spatial relationships and database queries, and how to analyze spatial data across two data sets.

What topics are taught in the lessons?

The lessons cover Tools for Exploring Geospatial Data, Tabular Relationships, Proximity Analysis, and Analysis Tools.

What skills will I gain from this course?

You will build skills in geospatial analysis, geospatial databases, GIS applications, spatial analysis, spatial databases, and spatial relations.

What is the difference between a joined and a related table?

Distinguishing a joined table from a related table is one of the questions this course addresses, and it explains how to join data by intersection or proximity as part of exploring tabular relationships.

What will I understand by the end of the course?

By the end, you will understand that spatial data provides many unique opportunities for data analysis that are not possible with tabular data sets.