Deleting columns/fields from polygon shapefile attribute table?

Question

I have a polygon shapefile that is loaded with old demographic data in its attribute file, I just received the new data today in xls format. What I want to do is just delete the old demo data from the existing shapefile by selecting the fields in the attribute table and right clicking delete. Then I would do a simple join using the ID numbers for each feature to add the new data from the new table then just export it out as a new shapefile. The problem is that for some reason I can not delete entire columns from the attribute table.

How would you go about stripping the data from this polygon shapefile?

Answer 1

• Use ArcToolbox > Data Management Tools > Fields > Delete Field.
• Choose your shapefile as the Input Table.
• Use the Select All button, then unselect the field(s) you want to keep.
• Hit OK.

ArcGIS 10 running on a 64 bit OS has a bug whereby you cannot delete columns using the right-click > delete field operation. Should be fixed in SP1 (I hope).

Answer 2

Deleting the fields is scary way of going about this. Are you absolutely sure you'll never need them? There are several non-destructive ways to accomplish your goal. One is to:

• load the shapefile and new table in ArcMap,
• join them on the ID field,
• right click the layer and choose Properties,
• on the Fields tab deselect all of the fields of the shapefile and click OK,
• right click the layer and export the data to a new file.

Only the checked fields will be exported to the new file and the old file will be preserved.

Answer 3

Make sure that you are not editing the shapefile when trying to alter its columns. Also, make sure other applications (like ArcCatalog) are not locking the shapefile.

Answer 4

My method is to make my join. then go to the layer properties and turn off all the fields I don't want. then if I need a subset of selected objects (maybe only the ones that got a join) make that selection. Then use the data export and export to a new shape file. The time involved is a fraction of the time for waiting for each attribute field to delete and update. Another trick to use if you don't go this way is to pause the draw window while deleting fields. this will save a bundle of time also. HTH