The Table Join operation is used to establish a connection between a vector layer in the map session and a data table using a common attribute. The relationship implemented between the variables in the data is one-to-one, depending on the number and type of the fields common to both inputs.
The Table Join tool can be selected by navigating the following path:
Tools > Vector Processing > Table Join
Once the Table Join tool is selected, a window appears in which you can select the datasets and parameters required to perform the operation.
The first section requires you to select the data layer and the data table required to implement the Table Join operation.
- Select spatial data from the session - Vector layer from the current session.
- Select data table to join - Dataset can be uploaded from three sources :
- My Data - Vector or Tabular data from 'My Data' module.
- Data Library - Vector or Tabular data from 'Data Library' module.
- Upload - Tabular data from the local system.
The second section requires you to select the fields to perform the join operation.
- Select Join Field from Vector Layer - Attribute to be joined
- Select Join Field from Data Table - Attribute to be joined
- Join Type - Select One-to-One join type to get singularly matched entries
- Discard records which could not be joined - If this checkbox is selected, only joined datasets will be shown on the output layer.
The attribute confirmation provides a summary of the operation, including the number of features that matched or did not match, as well as the execution time. The result can be viewed by clicking 'Submit' button, which redirects you back to the map session.
You can view the output after storing it. To save the output, you must enter the Output Layer Name and click on the Save Data button. The saved output will be added as a new layer in the current map session, where you can apply styling as required. This output layer will also be available in the 'My Data' section and can be used in any map session of interest.