I am new to QGIS and just downloaded QGIS 2.4 Chugiak.

I am practicing QGIS by using training manual, as mentioned in above subject.

I have questions in regard with the sentences in page 7:

You should then extract and save the following fields from the lines and points layers to their corresponding directories:

  • lines: “highway != ‘NULL”’ to roads, and “waterway != ‘NULL”’ to rivers
  • points: “place != ‘NULL”’ to places

How do I extract and save?

Can someone help me?


It seems your questions are just very basic GIS management operations. If you don't know how to do a select by attribute or export data, you should first read the general QGIS operation manual that explains it.

Nevertheless, in order to extract and save, do the following:

  1. Have your polyline and point layers loaded in your project table of contents
  2. Make sure the Attributes toolbar is active
  3. Select the relevant active layer in the table of contents (lines, or points, per the desired query)
  4. Click on the Select features using an expression tool
  5. Enter the query syntax you posted above in the Expression window, press Select, then Close
  6. You should have the relevant lines/point highlighted on your map
  7. Right-click the layer in the table of contents and choose Save as, then proceed to save the layer to the desired directory, while making sure that the Save only selected features box is checked.
  8. press Deselect features in the Attributes toolbar and repeat stages 3-7.

Good luck.

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