Loading Query creates massive rows???!!!

[nic2023]

Merge 1 connection with another Appended connection

What I did is: 

1) created a Connection sourced from a table contains approx. 7000 rows - a tab within the same Excel file. 

2) created an Appended Connection as a combined data - only to append table 2 & table 3, both are connections only, sourced from two separate tabs from the same Excel file - the number of rows of each tab is < 1500 rows. 

3) Merged 1) and 2) as a new query to be loaded. 

The issue I'm facing right now is:

The loading process seems taking forever, and the loading number of rows are now hitting >18 million rows!!?? while the raw data number of rows are only <10,000. 

The only thing I think I missed is when I create connectios, I didn't tick the box "Load to the Data Model" - but does this matter? 

Can I have some advice on this? Thank you. 

[ImkeF]

Hello @nic2023 ,
this will happen when the keys/join columns of your joined tables are not unique.
When you expand a field of such a joined table, one row in your (left) base table will be duplicated by the number of matching items in the joined table.
Technically, you can prohibit that by removing duplicates on the join columns of the joined tables.
But that might not return the correct results then, as there might be a reason for the multiple rows in there.
So you would have to go through each join, check for duplicates and decide how they must be handled from the business point perspective.

[nic2023]

Thank you so much @ImkeF 

I gave up using the worksheet within the same Excel file. 

 I ended up with using a separate raw data file, for another Power Query enabled file to get source from. Then load the connection/queries on the 2nd file. It works!