topic Re: Append Table to End of Table in Data Management Questions

Append Table to End of Table

MitchHolley1 — Fri, 27 Oct 2017 13:54:47 GMT

Is there a geoprocessing tool that literally appends one table (or columns) to the end of another? ESRI does something similar in their 'Symmetrical Difference' tool. See below for an example.

I know I could do this with a Python for loop and the 'Add Field' function, but that seems costly. I was hoping there was a geoprocessing tool that could do it for me.

Thanks for any help!

Re: Append Table to End of Table

JeffWard — Fri, 27 Oct 2017 14:47:51 GMT

There is the Append tool in the Data Management toolbox.

Re: Append Table to End of Table

JeffWard — Fri, 27 Oct 2017 14:48:50 GMT

Whoops, just saw you wanted to append columns not records.

Re: Append Table to End of Table

JeffWard — Fri, 27 Oct 2017 14:52:44 GMT

How about the Add Fields tool, it allows you to add several fields with the same tool. Or you can join the one table to the original if you have a common field.

Re: Append Table to End of Table

MitchHolley1 — Fri, 27 Oct 2017 14:58:19 GMT

Thanks for the reply, Jeff. I could Add Fields, but I already have data formatted and indexed in a table. So, ideally I would just add the entire table/data/columns to an existing table. I can't do a join because the two datasets are not related in any way.

Re: Append Table to End of Table

JeffWard — Fri, 27 Oct 2017 15:02:56 GMT

Are they identical spatially? Could you do a spatial join?

Re: Append Table to End of Table

JeffWard — Fri, 27 Oct 2017 15:08:57 GMT

Or is the new table empty? If so, you could just join them using a field of a common type (text, integer, float) and that would give you the empty columns tacked on at the end of the original columns then export that joined layer to another feature class.

Re: Append Table to End of Table

MitchHolley1 — Fri, 27 Oct 2017 15:08:57 GMT

No, these two datasets are tables actually and do not have a spatial reference.

Re: Append Table to End of Table

DanPatterson_Retired — Fri, 27 Oct 2017 15:43:43 GMT

arcpy.da.ExtendTable if you have numpy arrays... not a solution immediately probably, but keep it in mind

Re: Append Table to End of Table

JoshuaBixby — Fri, 27 Oct 2017 16:01:24 GMT

I am a bit confused. If the two datasets are not related in any way, how will you know you are successfully adding the data in the new columns to the data in the original columns? The screenshot you share has all NULLs for the right-hand columns, are you just wanting to add columns or add columns that already have data. If the latter, it gets back to my original question unless randomly mixing data between two data sets is OK.

Re: Append Table to End of Table

MitchHolley1 — Fri, 27 Oct 2017 16:10:26 GMT

I'm trying to accomplish what the Symmetrical Difference tool outputs, which is two tables merged to one. The left hand side of the table contains attributes from Table A and the right hand columns are Null or 0. Where there is no attributes to have for Table A, the right hand side of the table contains attributes from Table B while the left hand side of the table will be Null or 0.

I hope that's not too confusing.

Re: Append Table to End of Table

TedKowal — Fri, 27 Oct 2017 16:15:55 GMT

My 2 cents,

It sounds like you want to JOIN two tables. But the Key ingredient to make this successful is to have a common key between both tables; then you can see both tables side by side with the rows lined up. With out a common key, this is not doable under standard type practice without very creative logic.

Re: Append Table to End of Table

curtvprice — Sat, 28 Oct 2017 04:10:05 GMT

One approach that would be pretty efficient would be use Create Table (using table 2 as a template) and run a Join Field of table 1 with table 2. This is still a bit slow (Join Field can be slow with many records) but would be less work on your part.

Re: Append Table to End of Table

RichardFairhurst — Mon, 30 Oct 2017 02:12:24 GMT

What possible purpose is served by this type of join? If there is no relationship between the two tables (since you never match any of the records of Table A to Table B for any reason), why do you need this output? If it is a multi-field relationship I have a tool for dong that kind of match. It would help a lot to understand why you want this type of output before suggesting the best approach for accomplishing it, especially if in the end there actually is a relationship between the two tables that you are failing to tell us about.

Re: Append Table to End of Table

MitchHolley1 — Mon, 30 Oct 2017 13:12:59 GMT

I've mentioned twice in this thread that I need a output table that is similar to the one created by the Symmetrical Difference tool.

Re: Append Table to End of Table

JeffWard — Mon, 30 Oct 2017 15:14:19 GMT

Here is what I would do -

Join the two tables using a field of the same type - integer, text, float (it won't matter that none of the records join since your desired output is null field values for the right half of table A and null field values for the left half of table B) This step is so you have the fields from Table A tacked on to the right side of table B.
Export the joined table to a new table. This step makes all of the fields permanent in a new table.
Append Table B to the new table selecting "NO_TEST" in the Schema Type setting. Then map the fields to the corresponding fields in the new table. The Append tool is in Data Management - General toolbox.

This should get you what you are after if I understand your requirements correctly.

Re: Append Table to End of Table

TedKowal — Mon, 30 Oct 2017 15:49:15 GMT

Would not a simple cut and paste in an excel file do the same with less steps. Paste table a, Paste table b just to the right of table a

Re: Append Table to End of Table

MeredithBliss — Wed, 30 Dec 2020 18:10:02 GMT

I have run into this issue too. Rather than have to loop through and add 20-30 fields, I was hoping to copy a table, truncate the data, and then simply add the empty fields to the right of the data in existing feature class. From there I can use a dict join to move my data over. Data is too large for the join field tool to be efficient. The need is to simplify processing and scripting time.