Databricks Data Engineer Associate Question 176
Single answerYou are working with a DataFrame in Databricks that contains a column 'json_data' with JSON strings, and you need to parse these JSON strings into struct type to enable querying specific fields. Which of the following methods will correctly parse the JSON strings into structs in the 'json_data' column?
- A
Use the
from_jsonfunction, specifying the schema for the JSON structure. - B
Use the
to_jsonfunction to convert the strings into struct type. - C
Use the
explodefunction to parse the JSON strings into structs. - D
Use the
json_tuplefunction to parse the JSON strings into structs.
Show answer and explanation
Correct answer: A
Explanation
Parsing JSON strings into struct type in Databricks requires using the from_json function. This function takes a column with JSON strings and a schema defining the structure of the JSON data. Other functions, such as to_json, explode, and json_tuple, are not designed for this purpose and serve different functionalities.
- A. Correct.
Correct. The
from_jsonfunction is specifically designed to parse JSON strings into struct type by providing a schema that describes the JSON structure. - B. Incorrect.
Incorrect. The
to_jsonfunction is used to convert struct or map types into JSON strings, not the other way around. - C. Incorrect.
Incorrect. The
explodefunction is used to expand arrays or maps into multiple rows, but it does not parse JSON strings into structs. - D. Incorrect.
Incorrect. The
json_tuplefunction extracts values of specific keys in a JSON string as separate columns but does not convert the JSON string into struct type.