Dictionary Key Types | Dataford Interview Questions

Can tuple or list be the key for the dictionary?

In SQL terms, treat the two key columns as an ordered composite value and identify combinations that occur more than once. Include repeated combinations containing NULL values.

Output

One row per repeated key combination, with key_part_1, key_part_2, and occurrence_count.
Sort by occurrence_count descending, then key_part_1 ascending and key_part_2 ascending, with NULLs last.

Schema

key_candidates

Column	Type	Description
idPK	INT	Unique row identifier
key_part_1	VARCHAR(50)	First component of the composite value
key_part_2	INT	Second component of the composite value

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