Multiple choice technology databases

When utilizing a unique secondary index, how many AMP(s) are most probably accessed

  1. 1 AMP

  2. Multi - AMP

  3. 2 -AMP

  4. All-AMP
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A Unique Secondary Index (USI) value is hashed to determine which AMP contains the index subtable. Since USI enforces uniqueness, Teradata distributes USI rows across exactly 2 AMPs (one for the index, one as backup) to ensure single-AMP access during joins. This is more efficient than all-AMP or multi-AMP access, but more redundancy than 1-AMP.

Keep practicing — related questions