I have two tables in Azure SQL Server which, when I query directly using [SQL Query](https://i.stack.imgur.com/xpH3z.png) on the 'GroupID', gives me the expected output of 5,698 rows.

However, when I use **Merge Join** in SSIS
![Dataflow](https://i.stack.imgur.com/hRXgc.png) only 4,832 rows are merged using the **inner join**.

I've checked the metadata types (both are DT\_I4 and Sorted, Position 1):

> 
> "Name" "Data Type" "Precision" "Scale" "Length" "Code Page" "Sort Key
> Position" "Comparison Flags" "Source Component"
> 
> 
> "GroupID" "DT\_I4" "0" "0" "0" "0" "1" "" "INDEX"
> 
> 
> "Name" "Data Type" "Precision" "Scale" "Length" "Code Page" "Sort Key
> Position" "Comparison Flags" "Source Component"
> 
> 
> "GroupID" "DT\_I4" "0" "0" "0" "0" "1" "" "ASSETS by .........."
> 
> 
> 

as many posts talk about data type inconsistency or trying to join on strings. I have checked that the source data results in a full inner join but I just can't see what could be causing the SSIS inner join to not work as expected.

Any thoughts?

Thanks