How to Append Tables Based on a Condition

[Syndicate_Admin]

Hi there:

I have 2 tables containing participants for multiple events that we have hosted.  One table contains specific session by session attendance by individual ONLY for events that have multiple sessions.  The other table contains overarching event individual attendance across all events that were hosted (i.e. it includes BOTH events that are a single session AND those that are multiple sessions, but it does not break down which sessions an individual attended).  Overall, I want all of the attendance information combined into one table, so I would imagine that I need to append these 2 tables together.  HOWEVER, the 2nd table includes attendance across all events, and I only want to add the attendance to the single session events from the second table to the attendance for multiple session events in the first table.  How can I append them so it includes everything from the first table and only a subset of information from the second table? 

[Syndicate_Admin]

Description of problem statement is missing.

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[Syndicate_Admin]

I just updated it

[Syndicate_Admin]

Can you please both table structures alongwith some sample data?

[Syndicate_Admin]

Hi there:

I cannot provide real data, but here is a basic mock-up of what the two tables would look like.  And what I would want to do.  I only need the stuff in green from Table 2 added to Table 1 (and exclude from appending the cells in grey).

[Syndicate_Admin]

Solution made and uploaded to https://1drv.ms/x/s!Akd5y6ruJhvhuU6qFUfoiLBTTJkb?e=bpdoOy 

[Syndicate_Admin]

So how can I get the data from Table 2 in green to be in Table 1?

[Syndicate_Admin]

Use this - https://1drv.ms/x/s!Akd5y6ruJhvhuVBusqKbrvN_PjGK?e=aGHgGY 

[Syndicate_Admin]

Can you explain the steps of what you did?  I'm trying to learn what you did so I can apply it to the real data scenario I am dealing with.

[Syndicate_Admin · Accepted solution]

I have performed one Right Anti join. This join removed the matching rows from second table.

Removed all columns and expanded the table.

Now, I have a table which is having common rows removed from second table.

Appended this result to Output of Changed Type which was our original table.

Replace null in Session with Single-session.