If dataset A has 50 features and dataset B also 50 features, and they correspond one-to-one with no missing values for the key, how many features will you end up with after the join?

If dataset A has 50 features and dataset B also 50 features, and they correspond one-to-one with no missing values for the key, how many features will you end up with after the join?

• A. 0
• B. 75
• C. 100
• D. 50

Answer: (D)

When two datasets join on a key in a one-to-one relationship with no missing matches, each feature in one dataset pairs with exactly one feature in the other. The join produces one merged feature per pair, so the total number of features in the result equals the number of pairs. Since there are 50 features in each dataset and every feature has a unique match, you end up with 50 joined features. Note that the joined feature will contain attributes from both sides (potentially up to 100 attributes if there are no overlapping field names), but the count of features remains 50.

When two datasets join on a key in a one-to-one relationship with no missing matches, each feature in one dataset pairs with exactly one feature in the other. The join produces one merged feature per pair, so the total number of features in the result equals the number of pairs. Since there are 50 features in each dataset and every feature has a unique match, you end up with 50 joined features. Note that the joined feature will contain attributes from both sides (potentially up to 100 attributes if there are no overlapping field names), but the count of features remains 50.