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i'm trying to create a shapefile from an excel spreadsheet. the spreadsheet contains some data such as "unknown record" for which no lat/long can be obtained while the rest of the data is related to states of a country.when i add spreadsheet to arcgis it displays "null" value under lat long field in front of unknown record and when i create the shapefile the null values are replaced by "0" which causes an inconsistent map extent. i don't want to create a csv as it distorts my rest of the data. i tried placing "0" for the unknown record in lat long fields but in that case lat long wont show in add xy dialog box.please suggest a workaround so that my problem of inconsistent map extent is resolved.

  • Have you tried splitting the data into two imports. One with coordinates, and one without. If so, did the one with coordinates produce the "inconsistent map extent" warning? The non spatial data you try to process by a different method ie geo-coding. – GISI Jun 25 '15 at 8:45
  • yes, the one with co-oridnates produced the warning – Rehan Jun 25 '15 at 8:55
  • There's coordinates in your data that's either wrong or not in the coordinate system you think it's in. Confirm what your lat longs are in (ie WGS 1984) then hunt down the offending coordinate errors and fix them. – GISI Jun 25 '15 at 9:21
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    Do you wish to display the "unknown records" on the map? If so, where should they be placed geographically? – Stephen Lead Jun 29 '15 at 2:27
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Shapefiles use dBase databases, which do not support null values. Any null values in numeric fields are stored as 0 and strings as a blank space (regardless of software). If you want true null value support, you need storage format that is null capable (such as a file geodatabase).

Alternatively, you can import the records that do have coordinates and create the shapefile, then paste in/append the records that don't have coordinates to make sure they are created with null geometries (related: Joining blank shp with dBASE Table).

Note this resulting shapefile won't be valid, as a null geometry in a shapefile is technically an error and if repaired that record will be deleted (related: Polygon shapefile with null values? and Difference between empty and NULL geometry in file geodatabase?). Or you can just set the lat/long values to a known 'false' value, like Null Island.

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