Oracle Database Administration I — Question 48

What is true about non-equijoin statement performance? (Choose two.)

Answer options

• A. Table aliases can improve performance
• B. The BETWEEN condition always performs better than using the >= and <= conditions
• C. The join syntax used makes no difference to performance
• D. The BETWEEN condition always performs less well than using the >= and <= conditions
• E. The Oracle join syntax performs better than the SQL:1999 compliant ANSI join syntax

Correct answer: A, C

Explanation

Option A is correct because table aliases can simplify queries and improve readability, potentially affecting performance positively. Option C is also correct as the type of join syntax does not inherently influence performance. Options B and D are contradictory and incorrect as performance can vary based on context; thus, the BETWEEN condition does not consistently outperform or underperform the other conditions. Option E is incorrect because the performance of join syntax can vary depending on the specific query and database optimizations.