The correct answer is C. To ensure the same sample is returned each time a query is run .
The REPEATABLE keyword is used with a seed value to make sampling deterministic. This means Snowflake can return the same sample when the query is rerun with the same seed and the underlying data has not changed.
Why C is correct:
SELECT *
FROM table_A
SAMPLE BERNOULLI (10) REPEATABLE (123);
This returns a repeatable sample based on the seed value 123.
Why the other options are incorrect:
A). Returning a fixed number of rows uses SAMPLE ( < n > ROWS), not REPEATABLE.
B). REPEATABLE does not remove duplicates.
D). Block sampling is controlled with BLOCK or SYSTEM, not REPEATABLE.
Official Snowflake documentation reference:
Snowflake documentation explains that REPEATABLE or SEED specifies a seed value to make sample results repeatable.
Reference: Snowflake Documentation - SAMPLE / TABLESAMPLE; SnowPro Core Study Guide - SQL and Snowflake Objects.