What is the purpose of a normalized address_hash index in address deduplication?

What is the purpose of a normalized address_hash index in address deduplication?

• A. It stores the raw address string for quick lookups
• B. It enforces uniqueness of each address
• C. It helps quickly identify duplicates by using a normalized representation
• D. It slows down deduplication processes

Answer: (C)

The idea being tested is that deduplication relies on comparing a stable, standardized form of an address. A normalized address_hash index stores a hash of the address after normalization, so addresses that mean the same thing but are written differently (like “123 Main St.” and “123 Main Street”) map to the same value. When a new address comes in, you normalize it, compute its hash, and quickly check the index for that value. If there’s a match, it’s a duplicate; if not, it’s new. This approach speeds up detection because the index lets you find potential duplicates without scanning full text every time. The raw address string isn’t what this index uses for quick lookups, and the index alone doesn’t enforce uniqueness without an additional constraint, nor does it slow down deduplication—it's designed to accelerate it.

The idea being tested is that deduplication relies on comparing a stable, standardized form of an address. A normalized address_hash index stores a hash of the address after normalization, so addresses that mean the same thing but are written differently (like “123 Main St.” and “123 Main Street”) map to the same value. When a new address comes in, you normalize it, compute its hash, and quickly check the index for that value. If there’s a match, it’s a duplicate; if not, it’s new. This approach speeds up detection because the index lets you find potential duplicates without scanning full text every time. The raw address string isn’t what this index uses for quick lookups, and the index alone doesn’t enforce uniqueness without an additional constraint, nor does it slow down deduplication—it's designed to accelerate it.