Which functions will compute a 'fingerprint' over an entire table, query result, or window to quickly detect changes to table contents or query results? (Choose two.)

Question

Options

• AHASH(*)
• BHASH_AGG(*)
• CHASH_AGG(<expr>, <expr>)
• DHASH_AGG_COMPARE(*)
• EHASH_COMPARE(*)

• A
  90% (56)
• C
  2% (1)
• D
  6% (4)
• E
  2% (1)

Explanation

HASH(*) and HASH_AGG(*) are the two Snowflake-native functions built for change detection. HASH(*) computes a hash value across all columns of each row (using * as a shorthand for "all columns"), and when combined with an aggregate wrapper like MIN() or used alongside HASH_AGG, it enables table-level fingerprinting. HASH_AGG(*) is the purpose-built aggregate function that collapses all row hashes into a single hash value representing an entire table, query result, or window - making it the primary tool for quick change detection.

Why the distractors are wrong:

• C (HASH_AGG(<expr>, <expr>)) - HASH_AGG accepts expressions, but passing two named expressions is not the correct syntax for whole-table fingerprinting; * is required to cover all columns implicitly.
• D (HASH_AGG_COMPARE(*)) - this function does not exist in Snowflake.
• E (HASH_COMPARE(*)) - this function does not exist in Snowflake either; it's a plausible-sounding name designed to trip you up.

Memory tip: The two valid answers both follow the pattern HASH + (*) - the asterisk signals "everything." If a function name doesn't exist in real Snowflake (D, E), eliminate it immediately; and watch for real functions used with wrong argument patterns (C).

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