Table
Link Dialog
This interface is
used to create a new query layer that joins (link by a common attribute) the information of two layers.
Note that there are some conditions that must be met in order to link
two datasets:
- both datasets
must be at the same datasource (PostGIS, or a directory of
shapefiles and tabular files of .dbf format)
- the attribute used to link then must be of the same type (string or number).
Check how to add a Tabular File and how to Export a Layer to another datasource to meet the conditions above. Also there is a tool to export datasets from one datosource to another even before adding then to Terraview.
Link is
accessed through:
Rigth Click over a Layer (on Layer Explorer Tree) => Link...
- Dataset 1 frame:
- Name: The name of the Layer is shown
- Linked column: select the column (attribute) that will be used to link this dataset to the
- Dataset 2 frame:
- Name: select the dataset name to link with
- Alias: optionally give a nick name to this dataset.
- Optionally, click on the Data preview to check the first 5 rows of data before selecting the right column to link with.
- Linked Column: select the column that represent the same attribute of the dataset 1.
- Output Layer Name
- inform the output name of the new query layer.
- Help
- Displays the help.
- Ok
- It creates a new layer containing the sql generated by this dialog.
- Cancel
- It closes
the dialog without generating a new layer.
Limitations:
- OGR datasources (SHP and DBF files)
- Tthe
result will always be a 1 to 1 dataset due to how GDAL treats
the JOIN query [source];
- The files that are going to be linked must come from the same datasource, in this case, a directory;
- It is not yet possible to link with CSV files due to how GDAL treats a directory of CSV files [source]
- Microsoft Access