Python List and Dictionary Basics | Dataford Interview Questions

Tell me about how you use Python lists, list comprehensions, and dictionaries in data work.

For this SQL version, represent grouped record attributes in PostgreSQL using list-like and dictionary-like output structures. Include valid attribute names, retain NULL attribute values, and exclude rows without an attribute name.

Output

One row per record_id
Columns: record_id, metric_values, and metrics
Order values by metric_name within each record and rows by record_id ascending

Schema

data_records

Column	Type	Description
record_id	INT	Identifier for the record being summarized
metric_name	VARCHAR(50)	Attribute name used as a collection key
metric_value	VARCHAR(100)	Attribute value collected into the outputs

Your question is Python List and Dictionary Basics. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Tell me about how you use Python lists, list comprehensions, and dictionaries in data work.

Output

One row per record_id
Columns: record_id, metric_values, and metrics
Order values by metric_name within each record and rows by record_id ascending

Schema

data_records

Column	Type	Description
record_id	INT	Identifier for the record being summarized
metric_name	VARCHAR(50)	Attribute name used as a collection key
metric_value	VARCHAR(100)	Attribute value collected into the outputs

Your question is Python List and Dictionary Basics. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.