I have a shapefile with a few thousand features in it and a few dozen fields. One of these fields in the majority of cases has nothing in it, but in a few cases has non-null data - an URL string. These are the ones I am interested in looking at.
A google scouring turned up only three references total to the Viewer tool at all (two fme KB links, and a Google group post), none of which apply to this question.
I can specify $Fieldname and operator '!=' but what do I put in the right hand side of the tool to specify null values? I am assuming that the value is actually null or some kind of empty value, and not whitespace, invisible ASCII or some other junk...
I've tried 'null', '' and "" , and each time it filters nothing at all.
e.g.:
Restoring 21330 feature(s) from FME feature store file `d:\\temp\\FFS_1354146331484_5808' SHAPE::Testing: &History != ""(TestFactory): Tested 11109 input feature(s) -- 11109 feature(s) passed and 0 feature(s) failed
If I try to leave it 'empty' I get "Invalid or unspecified left side or right side of test expression"
Yes, I could use Workbench with a Tester or NullAttributeReplacer, convert it to a database table and use SQL, or open the data in ArcMap, but I would have thought FME Viewer would be able to do the same simle operation, faster.
I have had some luck with using "&Fieldname > X" (X can be zero or larger) which appears to be equivalent to "LENGTH(&fieldname) > 0", even though this is directly opposite to what the documentation says about how this works.
I'm sure most GIS users deal with null values in their data all the time, so this should be simple, but I don't see what I need to do in this case.
Any advice appreciated.
Regards,
Andrew Quee.
