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I've done this 100s of times and I can't understand why it won't work!

I'm trying to copy the first 8 digits of from a HUC 12 (Hydrologic Unit Code) to a new field, which represents a larger watershed HUC 8.

Field names:

  • WDB_HUC12 Text, length 14
  • HUC8 Text, length 8

  • Python Code: !WDB_HUC12![:7]

  • VBScript : Left([WDB_HUC12], 8)

No error message, but the field remains empty.

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Sorry about that Get Spatial, I saw your last comment after I deleted the question. I'm sure this will pop up again sometime in the future, good point. – Roy Jul 10 '12 at 15:54
No worries, just posted the answer. – Get Spatial Jul 10 '12 at 15:56
up vote 4 down vote accepted

Check to see if you have a single record selected somewhere in the table. If this is the case, the calculate operation will be working, but only on the selected record, not on the entire table. It will look like it is calculating and then nothing happens.

Simply clear the selected features, run the field calculator again, and it should work and be applied to the entire table.

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