QGIS/C3/Table-Joins-and-Spatial-Joins/English-timed

Time	Narration
00:01	Welcome to this tutorial on Table Joins and Spatial Joins in QGIS.
00:08	In this tutorial, we will learn to join the attribute tables of two data-sets having, common field , and same spatial data
00:19	Here I am using Ubuntu Linux OS version. 16.04
00:26	QGIS version 2.18
00:30	To follow this tutorial learner should be familiar with QGIS interface.
00:36	For the prerequisite QGIS tutorials, please visit this website.
00:42	Download the folder given in the Code files link, located below the player.
00:48	Extract the contents of the downloaded zip file and save it in a folder.
00:54	I have already downloaded the Code files, extracted and saved in a folder on the Desktop.
01:01	Double-click on the folder to open it.
01:04	Locate Stations.shp file in the extracted folder.
01:09	The Stations.shp file shows locations of meteorological stations or air stations across India.
01:17	Here we also have other files required to practice this tutorial.
01:23	Joining the attribute tables means, combining the attribute data between two data-sets.
01:30	There are two ways to join a table, Table Join that is, joining tables having one or more common column data.
01:40	Spatial Join means joining tables having same spatial data.
01:46	In this tutorial we will be demonstrating both the methods.
01:50	For more information please visit this website.
01:54	Open QGIS interface.
01:57	First, we will join attribute tables having common field.
02:02	Click on Add Vector Layer tool from the toolbar on the left-side.
02:07	Add Vector Layer dialog box opens.
02:10	Click on Browse button next to Dataset field. A dialog-box opens.
02:17	Navigate to Stations.shp file from the Code files folder on the Desktop.
02:22	Click on Open button.
02:25	In the Add vector layer dialog box, click on Open button.
02:30	The Stations.shp layer will be added in the Layers Panel.
02:35	The corresponding map appears on the canvas.
02:39	This map shows point features, corresponding to meteorological stations located in different states in India.
02:47	Let us open the attribute table for this layer.
02:51	In the Layers Panel, right-click on Stations.shp.
02:56	From the context menu choose Open Attribute Table option.
03:01	Attribute table opens.
03:03	Notice that data for only one attribute District is available.
03:10	Minimize the attribute table.
03:13	Now we will add another data-set which is a spreadsheet to the Layers Panel. This data set is in CSV format.
03:23	Click on Layer menu on the menu bar. Click on Add layer.
03:30	From the sub-menu click on Add Delimited Text Layer option.
03:35	A dialog box opens.
03:38	Click on Browse button located next to File Name field.
03:43	A dialog box opens.
03:46	Navigate to Rainfall.csv file from the Code files folder on the Desktop. Click on Open button.
03:54	In the Delimited Text File dialog box, select CSV as File Format.
04:01	Select Geometry definition as No geometry. Leave all other fields as such.
04:09	Click on OK button.
04:12	On QGIS canvas, Rainfall layer will be added in the Layers Panel.
04:18	Right-click on Rainfall layer.
04:21	Click on the Open Attribute Table from the context menu.
04:26	Attribute table opens. The attribute table has rainfall data from January to December for various districts.
04:37	Maximize the Stations attribute table and compare both the tables.
04:43	Please note, the District field is common in both Rainfall and Stations layers.
04:50	Now we will add the attribute data from Rainfall layer to Stations layer.
04:56	In the Stations attribute table there is only one column named District.
05:02	We will add the Rainfall data to the Stations attribute table.
05:07	Close the attribute tables.
05:10	Select Stations layer in the Layers Panel.
05:14	This layer will receive the new data from the Rainfall layer.
05:19	Right-click on Stations layer.
05:22	Click on the Properties option from the context menu.
05:26	Layer Properties dialog box opens. Click on Joins from the left panel.
05:33	In the new window, click on the plus sign, located on the bottom-left corner.
05:39	Add vector join dialog box opens.
05:43	Here we have options to choose for Join layer, Join field and Target field.
05:51	Join layer will be Rainfall layer, from which data will be added to Stations attribute table.
05:59	Here Rainfall layer is already selected.
06:03	Join field is the field or attribute in the Rainfall table to be joined.
06:10	In the Join field, select District from the drop-down.
06:15	Target field is the field to be joined in the Stations table.
06:20	In the Target field, District is already selected.
06:25	This field is common to both the tables.
06:29	Check the check-box for Choose which fields are joined.
06:34	The text-box below is now populated with all the columns and check-boxes.
06:41	Check the boxes for the columns January to Annual Average in the text box.
06:48	Click on OK button to close the Add vector join dialog box.
06:53	In Layer Properties dialog box, information about layer and columns joined are indicated at the top.
07:02	Click on Apply button, then OK button.
07:06	On the QGIS interface, as shown earlier open attribute table for Stations layer.
07:14	Observe that this table shows Rainfall data for all the stations.
07:20	Close attribute table.
07:23	Next, we will learn how to join attribute table of two data-sets by location.
07:30	Let us add another layer to the Layers Panel.
07:34	For this click on Add Vector Layer tool.
07:38	In the Add Vector Layer dialog box, click on Browse button.
07:43	Navigate to the Admin.shp from the Code files folder on the Desktop.
07:49	Click on Open button.
07:51	Again click on Open button in the Add Vector Layer dialog box.
07:56	Admin layer is now added to the Layers Panel.
08:00	Admin layer map opens showing the administrative state boundaries of India.
08:07	Click the Admin layer in the Layers panel.
08:11	Drag and bring it below Stations layer.
08:15	Now we can view the point features located in different States.
08:20	Open attribute table for Admin layer.
08:24	The attribute table shows information related to states.
08:29	Minimize the Admin attribute table. Again open the Stations attribute table.
08:36	Now we will join the attributes by location for Stations layer and Admin layer.
08:43	Close both the attribute tables.
08:47	Click on Vector menu.
08:48	Scroll down the menu and click on Data Management Tools.
08:53	From the sub-menu select Join attributes by location.
08:58	Join attributes by location dialog box opens.
09:02	Click on the drop-down for Target vector layer.
09:05	Here we need to specify the target vector layer for joining the attribute table.
09:12	In our case we need to add new data to the Stations layer.
09:17	Hence Stations layer is the Target Layer.
09:21	So we will select Stations [EPSG: 4326] from the drop-down as target layer.
09:29	Click on the drop-down for Join vector layer.
09:33	Here we have to select the layer which we want to join with the target layer.
09:40	Select Admin [EPSG: 4326] from the drop-down.
09:45	Here we have several options for joining the attributes.
09:50	We are interested to find the meteorological stations located in various states.
09:56	So under Geometric predicate, we will select within check-box. Scroll down.
10:04	Check the check-box for Open output file after running algorithm.
10:10	Leave the rest of the settings as default. Click on the Run button.
10:17	Status bar at the bottom shows the progress of the processing algorithm. Wait for the process to complete.
10:25	On the canvas, a new layer, Joined layer is added in the Layers Panel.
10:32	Right-click on the Joined layer and open attribute table.
10:37	This table contains all the attributes from Admin layer for each point on the Stations layer.
10:45	Every point feature has information about the state.
10:49	Close the attribute table.
10:52	To save the project, click on Project menu from the menu bar. Select Save As option.
11:01	Give an appropriate name and select a convenient location.
11:06	Click on Save button.
11:10	Let us summarize.
11:12	In this tutorial we have learnt to join the attribute tables of two data-sets having, common field, and same spatial data
11:22	As an assignment, Join the rainfall data from June to December with the stations data.
11:30	Use Rainfall.csv and Stations.shp files given in the Code files folder.
11:37	The completed assignment should look like this.
11:41	This video summarizes the Spoken Tutorial project. Please download and watch it.
11:48	The spoken tutorial project team conducts workshops and gives certificates. For more information please write to us.
11:58	Please post your timed queries on this forum.
12:02	The Spoken Tutorial Project is funded by NMEICT, MHRD Government of India.
12:10	This tutorial is contributed by Ambadas Maske from College of Engineering Pune, Snehalatha Kaliappan and Himanshi Karwanje from IIT Bombay. Thank you for joining.

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