Relationship Issue with a Summarized Table

[therightblue]

I'm having an issue with a summarized customer table. When I try to relate it to my transaction table by customer number, I get a many-to-many warning. But the summarized customer table only contains distinct customer numbers. The customer number column is also formatted as text. 

When I create a visualization using the customer table, I account 48414 and 000048414 only show once. Needless to say, I am perplexed. I need to create a many to one relationship with my transaction table. 

[PaulDBrown · Accepted solution]

@therightblue 

Are there any blank Values in the summarized table column you are using for the relationship?

[therightblue]

Yes, there is one blank value.