Error merge Inner

1. Null Values in Key Columns:

Even though you've filtered out null and blank values, there might still be rows where Clients_ID contains a null after filtering. Ensure that both tables you're merging are completely free of null values in the Clients_ID column by explicitly checking.

Solution: Double-check the Clients_ID column in both tables for null values after filtering. Use a conditional column or an additional filter step:

• In Power Query, use the Remove Empty option to remove any rows where Clients_ID is blank or null:
  • Select the Clients_ID column.
  • Click on Remove Rows -> Remove Blank Rows.

2. Data Type Mismatch:

Sometimes, the issue could be caused by mismatched data types. If Clients_ID is stored as a text column in one table and a different data type (like number or logical) in the other table, Power BI may have trouble merging them.

Solution: Ensure that both Clients_ID columns in the two tables have the same data type (preferably Text if you're dealing with ID fields). In Power Query, explicitly convert the data type:

• Select the Clients_ID column in both tables.
• Go to the Transform tab and choose Data Type -> Text.

3. Check Merge Logic:

The error could also be triggered if Power BI is trying to apply a logical operation (like a conditional join) where one of the values is null.

Solution: Ensure that your join condition in the merge step does not involve null values or any logic that expects a TRUE/FALSE outcome where null is present.

4. Check All Merge Conditions:

If your merge involves more than just the Clients_ID column, check if any other column in the merge step contains null values or has incompatible data types.

Hi clarainesgg 

Did Shravan133  's method solve your problem? If yes, could you please mark it as a solution? This will be of great help to other users experiencing similar problems. Thank you!

If you still have questions, please feel free to ask me.

Best Regards,
Yulia Xu