When you create a join,  attempts to match up columns as the keys in your join. For each set of join keys, you can review the following metrics related to the join.


Match percentage:

When you hover over the percentage of matches between key values, you can see the details that make up the calculation:

MetricDescription
All RowsTotal count of rows in the dataset
MatchesTotal count of values in the join key of the selected column with matching values in the join key of the other dataset.
Non-MatchesTotal count of values in the join key of the selected column with values that do not have a match in the join key of the other dataset.

The percentage is calculated by summing the count of matches for both datasets and dividing that by the total count of rows across both datasets:

(Matches_Current_Dataset + Matches_Joined-in-Dataset) / 
(All_Rows_Current_Dataset + All_Rows_Joined-in_Dataset)

Rows in output:

When you hover over the Rows in Output metric, you can see the following values:

MetricDescription
All RowsTotal count of rows in each dataset.
IncludedCount of rows from each dataset that are included in the output.
ExcludedCount of rows from each dataset that are excluded from the output.