Join dialog throws RegularRequirementNotMetFailure[join.columns.unequalCount] exception

Issue

When trying to create a Join with the following keys (two columns from a Sheet1 equals the same column from a Sheet2), I'm getting join.columns.unequalCount error.

Sheet1.A = Sheet2.A
Sheet1.B = Sheet2.A

Cause

This is expected behavior for the current product design, the Join constructor does not support such conditions.

Solution

To work around this limitation one could:

• Apply a Filter in Sheet1 using an EQUALS function on #Sheet1#A and Sheet1!B. Advanced Filtering Tutorial.
• Use an SQL Sheet with a corresponding SQL query that represents the desired Join operation. The query example:

SELECT * FROM Sheet1
JOIN Sheet2 ON Sheet1.A = Sheet2.A OR Sheet1.B = Sheet2.A