Answer: KEY, VALUE

The FLATTEN function in Snowflake returns a fixed set of columns when processing semi-structured data from VARIANT columns. According to the official Snowflake documentation and the community discussion with 100% consensus, the KEY column contains the key for maps or objects, and the VALUE column contains the actual value of the flattened element. These are two of the standard output columns. Option B (NODE), D (LEVEL), and E (ROOT) are not part of the standard FLATTEN output columns, which are SEQ, KEY, PATH, INDEX, VALUE, and THIS.

Author: LeetQuiz Editorial Team