Qgis 3 Spatial Query

4), and QGIS (3. NOTE: Version number indicates the update cycle when that theme was last updated. zip (36MB) Module 3 – Using Attribute and Spatial Queries for Data Exploration The Spatial. Previously, SRTM data for regions outside the United States were sampled for public release at 3 arc-seconds, which is 1/1200th of a degree of latitude and longitude, or about 90 meters (295 feet). These lectures and QGIS 2. The qgis tutorials for beginners pdf is 21 pages of screen captures an explanatory text to compliment the videos. 0 for Professionals which is available on Udemy for $20. 5 (25 ratings) Course Ratings are calculated from individual students' ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. qgis-SQV (Spatial Query with Values) A processing plugin for QGIS 3. 6 Desktop and customize the tools. Java Project Tutorial - Make Login and Register Form Step by Step Using NetBeans And MySQL Database - Duration: 3:43:32. How to do simple queries of geography with QGIS. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface. These criteria can be based on attribute queries (for example, parcels that are vacant) and spatial queries (for example, parcels that are within flood zones). It's possible to generate spatial queries from QGIS. Performing Spatial Queries¶ [ Download PDF A4 Letter]. Räumliche Abfrage Plugin¶. Spatial Query. First and foremost, QGIS 3 is a great tool. 2 extends the work begun in 3. In particular, for a verifiable query, the client must be able to prove that 1) all data returned from the SP originated at the DO and 2) the result set is correct and complete. This course uses the latest (as of 2/18) versions of PostgreSQL (10. Our primary QGIS trainer is Antony Scott. Amazon Relational Database Service (Amazon RDS) makes it easy to set up, operate, and scale a relational database in the cloud. If you want to find the 2 nd, 3 rd, or N th closest feature, use the Generate Near Table tool. The above query will use the bounding box of the polygon for comparison purposes. Browse and search flexible applications, frameworks, and extensions built with our powerful developer platform. General remark: Drawing the content of the map is processor intensive, QGIS seems to be more reliable if the composition is only drawn with exporting. Paolo Fogliaroni. layout:true. QGIS - QGIS is a popular desktop GIS software with a full suite of tools for performing spatial analysis, editing data, and creating printed maps. Today, we are going to show you how to clip a vector layer using polygon on QGIS. Hands on experience of QGIS 3. 0, the spatial queries operation can be performed with a tool called Select by Location. Performing Spatial Queries¶ [ Download PDF A4 Letter]. The Unload to Text page appears, showing the Schema wizard step. The following is a complete list of spatial relation operators available: INTERSECTS - (default) Return all documents whose geo_shape field intersects the query geometry. 3) ahead of the holiday season. These criteria can be based on attribute queries (for example, parcels that are vacant) and spatial queries (for example, parcels that are within flood zones). This course is intended to provide an introduction to spatial databases in general and PostGIS in particular to GIS professionals who are interested in expanding their skillset to multi-user enterprise level spatial databases. There are two ways to get information about addresses in Albuquerque, the Address Report and the Advanced Map Viewer. 0 for Professionals which is available on Udemy for $20. To do a spatial query to find a certain feature within a distance of another you can use a combination of attribute and spatial selections. I am using QGIS version 3. On the Database Home Page, click the Utilities icon, and then click the Data Load/Unload icon. GIS Workshop Concepts and Practice Nancy Warren, MPH With Contributions from: Nathan Heard, DSc Hilary Spindler, MPH Sarah Gutin Ryan Keating 2. Display the map only for placing the inset map or circles for accentuation. Perform the following steps: To do this, navigate to Layers | PostGIS Layers. The software and hardware described in this document are in most cases registered trademarks and are therefore subject to the legal. with this software you can create, edit, visualise, analyse and publish Download and setup ArcGIS 10. (With the Spatial Query tool you have not changed the dataset or created a new shapefile, it is only a visual change. Introduction to visualising spatial data in R Robin Lovelace (R. What is the largest municipality in the province, by area? This query brings a spatial measurement into the query condition. Petersburg, Florida, for a…. Get involved and help us write a better documentation. In QGIS, this functionality is available via the Spatial Query plugin. Preamble This document is the original user guide of the described software Quantum GIS. Spatial keyword query, Location-based services 1. I cant’t do it all in one post, but there are plenty of free resources available for you to learn QGIS if you need to and I offer a 10 hour course called QGIS 3. Part of the Esri Geospatial Cloud, Survey123 for ArcGIS is a complete, form-centric solution for creating, sharing and analyzing surveys. 3 mb Power Map is a 3D data visualization tool for Excel that provides an immersive experience for making discoveries in data that might never be seen in traditional 2D tables and charts. In particular, for a verifiable query, the client must be able to prove that 1) all data returned from the SP originated at the DO and 2) the result set is correct and complete. I cant't do it all in one post, but there are plenty of free resources available for you to learn QGIS if you need to and I offer a 10 hour course called QGIS 3. To do a spatial query to find a certain feature within a distance of another you can use a combination of attribute and spatial selections. 2 extends the work begun in 3. 0, the spatial queries operation can be performed with a tool called Select by Location. The data source for the queried layer here is stored in a SpatiaLite file. • No more split system data management-single source editing. Description This course is intended to provide an introduction to spatial databases in general and PostGIS in particular to GIS professionals who are interested in expanding their skillset to multi-user enterprise level spatial databases. The plugin dialog appears. For this case, geofilt and bbox won’t cut it. However, there is also functionality for editing vector data and a GRASS plugin to use the analytical functionality of the GRASS program [ 3 ] from within the QGIS GUI. select shops which have the address entered as London. Petersburg, Florida, for a…. He has trained over 100 people in using QGIS over the past few years, and regularly contributes to QGIS events, primarily in the South West. GeoServer is an open source server for sharing geospatial data. ANNOTATIONS ON We need to save a list of bridges within a provided area of interest to an Excel spreadsheet. Run the the query with the selected option as in. • Database interface that couples spatial data to the RDBMS allowing for high-performance access to all the data in there, spatial and non-spatial. Get involved and help us write a better documentation. The basic elements of the application GUI are similar to ArcMap's. Let's see how QGIS can be used to view the tables we created and populated in the previous section. If a join feature has a spatial relationship with multiple target features, then it is counted as many times as it is matched against the target feature. Select creating new selection, because we make a new selection 5. The COLUMN FILTER and QUERY BUILDER are essential User Interfaces that provide limited subsets of the querying and filtering functionality of QGIS. The Spatial Query Plugin allows you to make a spatial query (i. 7 Prerelease version 2019 QGIS 3. QGIS - QGIS is a popular desktop GIS software with a full suite of tools for performing spatial analysis, editing data, and creating printed maps. Spatial Query. Find Similar Locations Based on criteria you specify, the Find Similar Locations tool measures the similarity of locations in your candidate search layer to one or more reference locations. While our current projects may seem quite different from each other, they all have the same overarching goal: accessibility. Extract these and follow-along with me in the videos. In particular, for a verifiable query, the client must be able to prove that 1) all data returned from the SP originated at the DO and 2) the result set is correct and complete. Falko Schmid. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface. Other plots. In QGIS, this functionality is available via the Select by Location and Extract by Location. Ant has been working with QGIS since 2008 and provides QGIS expertise and training to MapAction - The humanitarian mapping charity. 4), and QGIS (3. Part of the Esri Geospatial Cloud, Survey123 for ArcGIS is a complete, form-centric solution for creating, sharing and analyzing surveys. Spatial queries allows you to select features in a layer by their spatial relationships (intersect, contain, touch etc. 0 to allow "dynamic" parameters for selected Processing algorithms. GeoServer is an open source server for sharing geospatial data. 0 for Professionals which is available on Udemy for $20. x choice from the QGIS folder in your Start menu. Giorgio De Felice. This course is intended to provide an introduction to spatial databases in general and PostGIS in particular to GIS professionals who are interested in expanding their skillset to multi-user enterprise level spatial databases. Select creating new selection, because we make a new selection 5. Open the map with the filtered layer in Map Viewer. The functionality is based on the GEOS library and depends on the selected source feature layer. 3 (12/22/2017) What’s new in ArcGIS API for Python v1. For this case, geofilt and bbox won’t cut it. Previously, SRTM data for regions outside the United States were sampled for public release at 3 arc-seconds, which is 1/1200th of a degree of latitude and longitude, or about 90 meters (295 feet). The tool can be found under the Vector Selection tool in the Processing Toolbox. 4), and QGIS (3. Developing a spatial query from QGIS. Giorgio De Felice. Dynamic parameters allow users to use expressions or field values to specify the value of a parameter while the algorithm executes, so e. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface. These criteria can be based on attribute queries (for example, parcels that are vacant) and spatial queries (for example, parcels that are within flood zones). We will be working with 2 datasets - a lines layer representing rivers and a point layer representing cities. [email protected] differentiate from traditional queries, the term spatial queries with integrity assurance is verifiable query. Extract these and follow-along with me in the videos. 0 for Professionals which is available on Udemy for $20. Load these three database layers into QGIS via the Add PostGIS Layers dialog, as usual. Any changes you make only apply to your view of the map (unless you own the map, in which case, you can save your changes). An older version number indicates. Run the the query with the selected option as in. These lectures and QGIS 2. Part of the Esri Geospatial Cloud, Survey123 for ArcGIS is a complete, form-centric solution for creating, sharing and analyzing surveys. I will assume that you have a basic working knowledge of QGIS. QGIS has a lot of documentation. The course workbooks. Amazon Relational Database Service (Amazon RDS) makes it easy to set up, operate, and scale a relational database in the cloud. One of the selection methods you can use to select features in a layer is to select features using an attribute query. Ant has been working with QGIS since 2008 and provides QGIS expertise and training to MapAction - The humanitarian mapping charity. By opening the. When you open a layer in the QGIS canvas, and then right-click the layer, you will see the Update SQL layer menu. This is a list of online raster tile servers based on OpenStreetMap data. QGIS Module 1 1. The Raster Calculator tool is intended for use in the ArcGIS Desktop application only as a GP tool dialog box or in ModelBuilder. 0 to allow “dynamic” parameters for selected Processing algorithms. a line layer may cross a region layer), Is Within (e. This tutorial goes in the line and helps the learners in analyzing those datasets on bars in their preferred locations with some spatial SQL in QGIS 3. 0, the spatial queries operation can be performed with a tool called Select by Location. What is the largest municipality in the province, by area? This query brings a spatial measurement into the query condition. Today, we are going to learn about query in QGIS. Display the map only for placing the inset map or circles for accentuation. Browse and search flexible applications, frameworks, and extensions built with our powerful developer platform. On VR Spatial Query for Dual Entangled Worlds With the rapid advent of Virtual Reality (VR) technology and virtual tour applications, there is a research need on spatial queries tailored for simultaneous movements in both the physical and virtual worlds. It opts for a monitoring environment, the privacy model that has been employed by location cloaking and other privacy-aware approaches. Räumliche Abfrage Plugin¶. Browse to the feature layer with the existing filter and click Filter. It establishes a base of understanding by presenting important primary insurance knowledge and develops core reinsurance concepts necessary for understanding the needs of insurers and solutions that reinsurance may provide. PostGIS Spatial Functions Demo¶ In order to demo PostGIS spatial functions, we’ll create a new database containing some (fictional) data. 7 Prerelease version 2019 QGIS 3. Power Map lets you plot geographic and temporal data visually, analyze that data in 3D, and create cinematic tours to share with others. Click Details and click Contents. An older version number indicates. The new data have been released with a 1 arc-second, or about 30 meters (98 feet), sampling that reveals the full resolution of the original measurements. The boundary information in the TIGER/Line Shapefiles is for statistical data collection and tabulation purposes only. Continuous, non-tiled, spatial database for adding spatial data to a relational database management system (RDBMS). Week 3 Bu ers and Regression Discontinuity Week 4 Rasters and D-in-D Week 5 Geocoding and QGIS Week 6 Cities Week 7 Climate Data and Spatial Interpolation Week 8 Lights at Night Week 9 Network Access and Market Access Week 10 Standard Errors in Space. Choose Google Maps Platform to create immersive location experiences and make better business decisions with accurate real-time data & dynamic imagery. There are several ways of approaching this problem, but the most efficient is below:. differentiate from traditional queries, the term spatial queries with integrity assurance is verifiable query. The Raster Calculator tool is intended for use in the ArcGIS Desktop application only as a GP tool dialog box or in ModelBuilder. For the names of the physical servers that serve openstreetmap. You will find documentation for every QGIS long term release on the respective documentation website. The result of web-based GIS portal supports spatial and non-spatial database of tourist attraction and tourist service data with attractive user interface. Designed for interoperability, it publishes data from any major spatial data source using open standards. This course is intended to provide an introduction to spatial databases in general and PostGIS in particular to GIS professionals who are interested in expanding their skillset to multi-user enterprise level spatial databases. 4), and QGIS (3. Let's see how QGIS can be used to view the tables we created and populated in the previous section. If you want to find the 2 nd, 3 rd, or N th closest feature, use the Generate Near Table tool. This menu is very useful when we need to select some data using SQL query syntax. The new data have been released with a 1 arc-second, or about 30 meters (98 feet), sampling that reveals the full resolution of the original measurements. The approach is based on neighborhood information derived from the Voronoi diagram of the underlying spatial data set and can handle fundamental spatial query types. The functionality is based on the GEOS library and depends on the selected source feature layer. The fifth module is entitled to "Spatial Data Analytics", which is one of the four disciplines related to spatial data science. Performing Spatial Queries¶ [ Download PDF A4 Letter]. Introduction to visualising spatial data in R Robin Lovelace (R. To do a spatial query to find a certain feature within a distance of another you can use a combination of attribute and spatial selections. You will find documentation for every QGIS long term release on the respective documentation website. This plugin adds two algorithms to the processing tool box. These data types are based on latitude and longitude coordinates of the spatial object such as point, line, polygon, etc. Load the Spatial Query plugin in the Plugin Manager (see The Plugins Dialog) and click on the Spatial Query icon, which appears in the QGIS toolbar menu. Download with Google Download with Facebook or download with email. This menu is very useful when we need to select some data using SQL query syntax. differentiate from traditional queries, the term spatial queries with integrity assurance is verifiable query. QGIS tutorial topic: Learn the Bare Essentials of Spatial Analysis - map overlay, spatial data query & buffering in GIS 4. There is a collection of plugins ready to be used, available to download. Spatial Query Plugin¶ The Spatial Query Plugin allows you to make a spatial query (i. the buffer size can be dynamically calculated for each individual feature buffered. The main focus of QGIS is interactive two dimensional viewing of spatial data. The Spatial {Query} Lab's mission is to make spatial technology, education, and information accessible to everyone. There are several ways of approaching this problem, but the most efficient is below:. This course uses the latest (as of 2/18) versions of PostgreSQL (10. SQL spatial data types. 6 Desktop and customize the tools. Select creating new selection, because we make a new selection 5. I cant’t do it all in one post, but there are plenty of free resources available for you to learn QGIS if you need to and I offer a 10 hour course called QGIS 3. These algorithms allow the user to perform a spatial query between a polygon layer and and an additional intersecting vector layer of any geometry type. See spatial query tutorial how to use Select by location with some examples. I am going to show you how to use the Update SQL Layer menu on QGIS. Open the map with the filtered layer in Map Viewer. 0, the spatial queries operation can be performed with a tool called Select by Location. In particular, for a verifiable query, the client must be able to prove that 1) all data returned from the SP originated at the DO and 2) the result set is correct and complete. NOTE: Version number indicates the update cycle when that theme was last updated. Video created by Yonsei University for the course "Spatial Data Science and Applications". a line layer may cross a region layer), Is Within (e. An older version number indicates. This short video uses the example of the energy efficiency of buildings to demonstrate how to make INSPIRE work for you. I will assume that you have a basic working knowledge of QGIS. zip (36MB) Module 3 - Using Attribute and Spatial Queries for Data Exploration The Spatial. First and foremost, QGIS 3 is a great tool. If any distance i. a line layer may cross a region layer), Is Within (e. QGIS plugins web portal. Check are within option below geometric predicate. It's possible to generate spatial queries from QGIS. , select features) in a target layer with reference to another layer. NOTE: Version number indicates the update cycle when that theme was last updated. By opening the. Description This course is intended to provide an introduction to spatial databases in general and PostGIS in particular to GIS professionals who are interested in expanding their skillset to multi-user enterprise level spatial databases. The main focus of QGIS is interactive two dimensional viewing of spatial data. QGIS Module 1 1. Perform the following steps: To do this, navigate to Layers | PostGIS Layers. 0 for Professionals which is available on Udemy for $20. This course uses the latest (as of 2/18) versions of PostgreSQL (10. It opts for a monitoring environment, the privacy model that has been employed by location cloaking and other privacy-aware approaches. Add PostGIS data to QGIS. 0, the spatial queries operation can be performed with a tool called Select by Location. Spatial Query. Paolo Fogliaroni. , select features) in a target layer with reference to another layer. Let's see how QGIS can be used to view the tables we created and populated in the previous section. It opts for a monitoring environment, the privacy model that has been employed by location cloaking and other privacy-aware approaches. Performing Spatial Queries (QGIS3)¶ Spatial queries are core to many types of GIS analysis. 4), and QGIS (3. A community dedicated to everything GIS (Geographic Information Systems). ANNOTATIONS ON We need to save a list of bridges within a provided area of interest to an Excel spreadsheet. These lectures and QGIS 2. the buffer size can be dynamically calculated for each individual feature buffered. Download with Google Download with Facebook or download with email. NOTE: Version number indicates the update cycle when that theme was last updated. For anyone who might benefit from it, I'll post a HTML legend for CORINE Land Cover (CLC) Classes, which I tailored for HTML labelling of CLC-Rasters embeded in my QGIS via WMS. The online registry supports anonymous (guest) access, but also permits the user to register for additional services, such as the export of the entire Dataset. 3 (12/22/2017) What’s new in ArcGIS API for Python v1. Spatial Query Plugin¶ The Spatial Query Plugin allows you to make a spatial query (i. 3) ahead of the holiday season. The COLUMN FILTER and QUERY BUILDER are essential User Interfaces that provide limited subsets of the querying and filtering functionality of QGIS. 0 for Professionals which is available on Udemy for $20. If you want to find the 2 nd, 3 rd, or N th closest feature, use the Generate Near Table tool. x choice from the QGIS folder in your Start menu. The plugin dialog appears. Intermediate GIS with QGIS and PostGIS by Introduction to GIS Fundamentals by select st_area(geom) from polygon_filename. Spatial queries are core to many types of GIS analysis. 1), PostGIS (2. This wizard step displays a Schema list, in which HR is selected. All documentation is in English but some documents such as the user guide are also available in other languages. Spatial queries allows you to select features in a layer by their spatial relationships (intersect, contain, touch etc. Ant has been working with QGIS since 2008 and provides QGIS expertise and training to MapAction - The humanitarian mapping charity. Select park_polygon as comparing features. Hands on experience of QGIS 3. This is somewhat of a trick, but you can use Solr’s range query syntax for this by supplying the lower-left corner as the start of the range and. As we can appreciate, QGIS 3 as a modern GIS platform that’s integrated with the best spatial algorithms and the most appropriate data formats to you to process your data in no-time. ) with features from another layer. QGIS plugins web portal. However, there is also functionality for editing vector data and a GRASS plugin to use the analytical functionality of the GRASS program [ 3 ] from within the QGIS GUI. 2 extends the work begun in 3. layout:true. As we can appreciate, QGIS 3 as a modern GIS platform that’s integrated with the best spatial algorithms and the most appropriate data formats to you to process your data in no-time. net,spatial-query I have used this string and tested it with string concatenation. This tool creates a new shapefile whereas the Spatial Query only displays the new information. If you're. Spatial queries allows you to select features in a layer by their spatial relationships (intersect, contain, touch etc. In QGIS, this functionality is available via the Select by Location and Extract by Location. 4 User Guide (Read and download PDF) English. Petersburg, Florida, for a…. This is somewhat of a trick, but you can use Solr’s range query syntax for this by supplying the lower-left corner as the start of the range and. • No more split system data management-single source editing. Performing Spatial Queries¶ [ Download PDF A4 Letter]. These lectures and QGIS 2. , select features) in a target layer with reference to another layer. The tool can be found under the Vector Selection tool in the Processing Toolbox. The Spatial Query Plugin allows you to make a spatial query (i. INTRODUCTION An increasing number of Spatial Keyword (SK) query techniques have been proposed in the literature [2, 3, 5, 6]. You will find documentation for every QGIS long term release on the respective documentation website. Let's see how QGIS can be used to view the tables we created and populated in the previous section. The approach is based on neighborhood information derived from the Voronoi diagram of the underlying spatial data set and can handle fundamental spatial query types. While our current projects may seem quite different from each other, they all have the same overarching goal: accessibility. 4 User Guide (Read and download PDF) English. zip (36MB) Module 3 - Using Attribute and Spatial Queries for Data Exploration The Spatial. 0 for Professionals which is available on Udemy for $20. I will assume that you have a basic working knowledge of QGIS. Turbocharge your Python scripts with ArcGIS API for Python v1. This tool creates a new shapefile whereas the Spatial Query only displays the new information. Goal • Understand important GIS concepts and how to utilize them through Quantum GIS (QGIS), an open source software package 3. They include contains (e. Our primary QGIS trainer is Antony Scott. 0 for GIS professionals will provide all the background that is necessary but it is not a formal pre-requisite. “The ARe designation provides a solid foundation for those entering or interested in the reinsurance field. Load the Spatial Query plugin in the Plugin Manager (see The Plugins Dialog) and click on the Spatial Query icon, which appears in the QGIS toolbar menu. ) Click the Vector menu at the top of the QGIS program, mouse-over Geoprocessing Tools, and click Clip. But as you know it is not safe to use this to format an sql command. So I can't see any difference in the data to explain the problem. 7 Prerelease version 2019 QGIS 3. Spatial keyword query, Location-based services 1. Spatial queries are core to many types of GIS analysis. Let's see how QGIS can be used to view the tables we created and populated in the previous section. If any distance is involved, your data must be projected. You will find documentation for every QGIS long term release on the respective documentation website. Files have been downloaded times. In QGIS, this functionality is available via the Select by Location and Extract by Location Processing tools. Petersburg, Florida, for a…. shp and airports. • No more split system data management-single source editing. It'll be the QGIS Desktop 3. QGIS Documentation. Spatial queries are core to many types of GIS analysis. Other plots. This is performed using the Select By Attributes tool, which is described here. “The ARe designation provides a solid foundation for those entering or interested in the reinsurance field. Select creating new selection, because we make a new selection 5. Support for these spatial types in ArcGIS is still maturing, and in this course, we will assume that the way to make a spatial query is through Select Layer By Location. As open source software it is free to download and use, making it a good option after you leave the University. The purpose of this post is to teach spatial databases and not QGIS. Geometry spatial data type. It'll be the QGIS Desktop 3. Power Map lets you plot geographic and temporal data visually, analyze that data in 3D, and create cinematic tours to share with others. GST 102 - Spatial Analysis. Information on how to access the service is available in Guidance Note 7-3: EPSG Registry Developers Guide. 7 Prerelease version 2019 QGIS 3. These data types are based on latitude and longitude coordinates of the spatial object such as point, line, polygon, etc. To do a spatial query to find a certain feature within a distance of another you can use a combination of attribute and spatial selections. 0 for Professionals which is available on Udemy for $20. This menu is very useful when we need to select some data using SQL query syntax. The plugin dialog appears. with this software you can create, edit, visualise, analyse and publish Download and setup ArcGIS 10. All documentation is in English but some documents such as the user guide are also available in other languages. A community dedicated to everything GIS (Geographic Information Systems). Getting Better with QGIS Getting Better with QGIS We had the pleasure of hosting Kurt Menke of Bird’s Eye View GIS at Spatial Networks headquarters in St. This tool creates a new shapefile whereas the Spatial Query only displays the new information. Today, we are going to show you how to clip a vector layer using polygon on QGIS. The COLUMN FILTER and QUERY BUILDER are essential User Interfaces that provide limited subsets of the querying and filtering functionality of QGIS. Select park_polygon as comparing features. Tag: c#,sql,asp. Support for these spatial types in ArcGIS is still maturing, and in this course, we will assume that the way to make a spatial query is through Select Layer By Location. It is not intended for use in scripting and is not available in the ArcPy Spatial Analyst module. By opening the. The basic elements of the application GUI are similar to ArcMap's. Performing Spatial Queries¶ [ Download PDF A4 Letter]. QGIS has a lot of documentation. Intermediate GIS with QGIS and PostGIS by Introduction to GIS Fundamentals by select st_area(geom) from polygon_filename. The third module is "Geographic Information System (GIS)", which is one of the four disciplines for spatial data science.