in power bi is this true, always ensure that both of the columns that you are using to participate in a relationship are sharing the same data type. Your model will never work if you try to build a relationship between two columns, where one column has a text data type and another column has an integer data type.
this statement is in optimize model performance - reduce relationship cardinality learning module
and in check your knowledge section,
Which of the following statements about relationships in Power BI Desktop is true?
1.Relationships can only be created between columns that contain the same data type.
2.Relationships can only be created between tables that contain the same number of rows.
3.Relationships can be created between tables that contain different types of data.
for this question the answer is 3.Relationships can be created between tables that contain different types of data.
which one is correct.