Tool to add Columns if they do not exist

[pkuenstler]

I suggest an additional tool that would allow adding columns to the data, if and only if they do not exist already.

Currently working with data that has a dynamic set of columns can be a bit tiresome as the Select tool will not allow to select columns that have not been witnessed in the data.

Adding a tool that would ensure that certain columns are available downstream can currently be achieved by:

1. 'Append Fields' tool with a 'Text Input' tool which will always append the fields, renaming them on the fly if needed
2. 'Union' tool with a 'Text Input' tool

Both options do not seem straight forward and I expect have a performance impact.

A separate tool to achieve this seems the more user friendly and performance oriented way.

[soncoku]

I'm having the same exact problem.

Did you manage to solve it??

[pkuenstler]

I am still using the Append Fields tool. It works but is not nice.

[soncoku]

I'm using that too for the moment, it does the job.

[PangHC]

i face same issue.

i fixed it via text input tool + union tool

explain further,

1. Create text input , only create field, no rows.(need not to filter later)

2. Union it with your data.

and that it. 

btw, i not understand how the append work...

[Bharadwaj]

The union fix helped. Thanks 

[BobR]

This will make cleaner code. My code is littered with text input -> union -> filter for this purpose.

I think adding a tool that looks like select "or" adding the feature to the select tool would be great.