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Deleting Attributes from Table

May 12 2010 | 1 comment
Categories: Map Data

I downloaded a hydrology polyline shapefile from the USGS website and when I examined the attribute table I saw that it included coastline, paths, and water pipeline as well as streams and rivers. For my project purpose I only need rivers and streams and the other data might hinder my analysis. I tried selecting and deleting the unwanted attributes but wasn't able to. Is there any other way to do this? Thank you for your time.

Mapping Center Answer:

It actually sounds like you need to delete some features (i.e., the ones that are not streams and rivers) rahter than deleting some attributes.  If this is the case, first start an Edit session, then use the Select by Attributes tool to find the features that are not streams and rivers, and then delete them.  Save your edits and the feature class will now only contain those features that are streams and rivers.  You can check to make sure that you have only the streams and rivers by opening the attribute table and checking the values that identify the features as coastlines, paths, water pipelines, streams and rivers -- you should now only see streams and rivers in thsi field.

select and export posted by David Barnes on May 13 2010 7:37AM
Another way is to select the features you want to keep (using Select by Attribute, for example), then right-click on the layer in the TOC, select Data > Export Data and export the selected features to a new layer.
Main advantage here is you're not affecting the original data source, if that's a concern. You can do this outside an edit session. :)

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