topic Re: How do I convert a field value to NULL? in Data Management Questions

How do I convert a field value to NULL?

StewartGalloway — Mon, 12 Feb 2018 20:28:11 GMT

How do I convert a field value to NULL? I tried Calculate. Not sure how to use Python = "none" but I could not get it to work.

Thanks.

Stew

Re: How do I convert a field value to NULL?

AbdullahAnter — Mon, 12 Feb 2018 22:53:43 GMT

Do you check if the field is nullable or not?

Re: How do I convert a field value to NULL?

JamesMacKay3 — Mon, 12 Feb 2018 22:57:00 GMT

Try "None" without surrounding quotes (it's also case-sensitive).

Re: How do I convert a field value to NULL?

DanPatterson_Retired — Mon, 12 Feb 2018 23:19:02 GMT

In summary, make sure the field is nullable and you use the python parser when typing ... None ....

since None is a python object for sure... not sure about other parsers.

Re: How do I convert a field value to NULL?

JoeBorgione — Mon, 12 Feb 2018 23:59:06 GMT

Null in VB.

Re: How do I convert a field value to NULL?

DanPatterson_Retired — Tue, 13 Feb 2018 00:16:21 GMT

don't encourage vb Joe

Re: How do I convert a field value to NULL?

JayantaPoddar — Tue, 13 Feb 2018 06:34:02 GMT

maybe something like this.

In above example, the value of 0 is replaced by <Null>

Re: How do I convert a field value to NULL?

TedKowal — Tue, 13 Feb 2018 15:37:14 GMT

😮 But it is so readable and understandable unlike Python

Re: How do I convert a field value to NULL?

Lake_Worth_BeachAdmin — Tue, 13 Feb 2018 16:34:00 GMT

Python is very user friendly

Re: How do I convert a field value to NULL?

StewartGalloway — Wed, 14 Feb 2018 14:48:30 GMT

Reply to all,

Thanks very much for the help! There were two parts to the solution using the Field Calculator to enter "None".

1) case-sensitive
2) use the python parser

Stew

Re: How do I convert a field value to NULL?

DanPatterson_Retired — Wed, 14 Feb 2018 15:02:39 GMT

Stewart... also remember in Python and for fields that are 'nullable'

there is only one .... None ....

you use it for all field types... text, numbers etc

https://community.esri.com/blogs/dan_patterson/2015/04/17/none-isntnor-is-0-or-1-more-explorations-into-geometry

https://community.esri.com/blogs/dan_patterson/2016/11/03/before-i-forget-18-those-pesky-null-things

https://community.esri.com/blogs/tilting/2015/05/29/whats-in-your-feature-class-nothing-null-or-empty

and who said there is nothing more to learn about nothing

Re: How do I convert a field value to NULL?

TedKowal — Wed, 14 Feb 2018 16:02:19 GMT

Just like Perl! Even though I respectfully disagree! I find it to be an awful language...but who am I to say... the masses embraced it so in order to progress I have to deal with it!

Re: How do I convert a field value to NULL?

DanPatterson_Retired — Wed, 14 Feb 2018 16:09:32 GMT

Come on Ted... you are getting behind... more on the horizon for instance... https://julialang.org/

Re: How do I convert a field value to NULL?

TedKowal — Wed, 14 Feb 2018 20:12:53 GMT

That looked interesting.... I did like Fortran

Re: How do I convert a field value to NULL?

FranciscoCosta1 — Thu, 10 May 2018 23:47:31 GMT

If you are trying to handle missing data usually Data Scientists like me advise to use np.nan because of this:

python - What is the difference between NaN and None? - Stack Overflow

for consistency i would recommend this:

myfieldvalue=np.nan otherwise you can do else.

Re: How do I convert a field value to NULL?

DanPatterson_Retired — Fri, 11 May 2018 00:01:19 GMT

This has also been brought up before in the context of geometry definitions, but probably too late to implement any changes

https://community.esri.com/blogs/dan_patterson/2018/01/12/point-of-view-on-points

Re: How do I convert a field value to NULL?

FranciscoCosta1 — Fri, 11 May 2018 00:18:02 GMT

Ok, really wasn't considering the point(geometry) fields. So while for non point(geometry) fields perhaps is a good idea to consider np.nan, for point(geometry) fields go with math.nan accordingly.

Re: How do I convert a field value to NULL?

DanPatterson_Retired — Fri, 11 May 2018 00:23:23 GMT

for vector geometry, I simply use numpy arrays with np.nan and I can convert back and forth between arc* geometry using a variety of means.

But I suspect this should be a separate thread

Re: How do I convert a field value to NULL?

FranciscoCosta1 — Fri, 11 May 2018 00:30:23 GMT

hence what i originally posted accordingly