Merging two features in QGIS is a common task for combining adjacent or overlapping features of the same layer into a single feature. This process is typically done using the Merge Selected Features tool.
To merge features in QGIS, you need to select the features you want to combine and then use the appropriate tool from the digitizing toolbar.
Prerequisites
Before you can merge features, ensure that you are in editing mode for the layer containing the features you wish to merge. You will also need access to the Advanced Digitizing Toolbar.
- Enable Editing: Toggle editing mode for your target layer.
- Show Advanced Digitizing Toolbar: Right-click on any QGIS toolbar area and ensure the Advanced Digitizing Toolbar is checked and visible. As indicated by the provided video reference, checking this toolbar makes the necessary tool available.
Step-by-Step Guide to Merging Features
Once the prerequisites are met, follow these steps:
- Select the Features: Using the Select Features by Area or Single Click tool (or another selection method), select the two or more features you intend to merge into a single feature. Ensure only the features you want to merge are selected.
- Click Merge Selected Features: With the desired features selected, locate the Merge Selected Features button on the Advanced Digitizing Toolbar. According to the video reference, you click this button after selecting your features. This tool looks like two overlapping polygons with an arrow pointing to one larger polygon.
- Handle Attributes: A dialog will appear allowing you to choose which attributes from the original features should be retained for the new, merged feature. You can select attributes from one of the original features, average them (for numeric types), sum them (for numeric types), or enter new values manually.
- Confirm Merge: After setting the attributes, confirm the merge operation. The selected features will be combined into a single feature.
- Save Edits: Don't forget to save your edits using the Save Layer Edits button to make the change permanent.
By following these steps, you can effectively merge multiple features into a single one in QGIS, simplifying your dataset and analysis.
