Exam Certified Data Engineer Associate topic 1 question 71 discussion

https://docs.databricks.com/en/ingestion/auto-loader/schema.html#how-does-auto-loader-schema-inference-work By default, Auto Loader schema inference seeks to avoid schema evolution issues due to type mismatches. For formats that don’t encode data types (JSON and CSV), Auto Loader infers all columns as strings (including nested fields in JSON files).

Its B "By default, Auto Loader schema inference seeks to avoid schema evolution issues due to type mismatches. For formats that don’t encode data types (JSON and CSV), Auto Loader infers all columns as strings (including nested fields in JSON files). For formats with typed schema (Parquet and Avro), Auto Loader samples a subset of files and merges the schemas of individual files. This behavior is summarized in the following table:" https://docs.databricks.com/en/ingestion/auto-loader/schema.html

https://docs.databricks.com/en/ingestion/auto-loader/schema.html#how-does-auto-loader-schema-inference-work

The correct answer is: B. JSON data is a text-based format JSON data is a text-based format that uses strings to represent all values. When Auto Loader infers the schema of JSON data, it assumes that all values are strings. This is because Auto Loader cannot determine the type of a value based on its string representation. https://docs.databricks.com/en/ingestion/auto-loader/schema.html For example, the following JSON string represents a value that is logically a boolean: JSON "true" Use code with caution. Learn more However, Auto Loader would infer that the type of this value is string. This is because Auto Loader cannot determine that the value is a boolean based on its string representation. In order to get Auto Loader to infer the correct types for columns, the data engineer can provide type inference or schema hints. Type inference hints can be used to specify the types of specific columns. Schema hints can be used to provide the entire schema of the data. Therefore, the correct answer is B. JSON data is a text-based format.