Exam 1z0-071 topic 1 question 3 discussion

D. Table aliases can improve performance. Table aliases can improve performance by reducing the amount of parsing needed to execute the query. C. The Oracle join syntax performs better than the SQL:1999 compliant ANSI join syntax in Oracle 18c. Oracle's join syntax can result in better performance in certain scenarios as it allows the optimizer to understand the join order and access paths more effectively. Therefore, options C and D are correct. Options A, B, and E are incorrect.

Those who answered D - provide a link with the Oracle documentation as a prove! E - is correct.

DE are correct

A and B are false, no discussion. C. Oracle's query optimizer internally rewrites both syntaxes into the same execution plan. The decision on how to execute the join—nested loop, hash join, merge join, etc.—is based on statistics, indexes, and optimizer settings, not on the join syntax itself. D. Oracle's SQL parser and optimizer are designed to handle fully qualified table names just as efficiently as aliases. The use of aliases affects only the textual complexity of the query, not the underlying parsing or optimization time in any meaningful or measurable way.

Oracle's official stance: Oracle documentation explicitly states that the SQL:1999-compliant join syntax does not offer any performance benefits over the Oracle-proprietary join syntax that existed in prior releases

D, E with no doupt

D. Table aliases can improve performance. Most Voted E. The join syntax used makes no difference to performance.

D. Table aliases can improve performance. Most Voted E. The join syntax used makes no difference to performance.

A and B states ALWAYS - which is not always the case. C: The join syntax doesn't make much difference with performance. D: That's correct; it helps the optimizer E: this makes sense to me - The joint syntax doesn't make a difference.

According to some papers and IA, these must be the better options...

options D and E are correct Options C are incorrect because the SQL:1999–compliant join syntax does not offer any performance benefits over the Oracle-proprietary join syntax that existed in the earlier releases.

i find D and E a little bit contradictory, do aliases come under join syntax?

D. Table aliases can improve performance. E. the difference related to performance that can be experimented between the two join syntax is minimum since Oracle optimizes internally both manners in a similar way

C and D is true. C is true because oracle Join does perform better. D is true. Table aliases improve the I/O. Refer: https://docs.oracle.com/middleware/1221/bip/BIPDM/best_practices.htm E is false. It does affect performance. Refer: https://docs.oracle.com/cd/F49540_01/DOC/server.815/a67781/c20c_joi.htm

Table alias makes it easy for the parser to look up the columns in their respective tables. "Join" or "Where T1.id=T2.id" conditions have no difference in performance, though join is recommended to be used as the new syntax.

I vote for answers C and E. To be honest, I don't know how good they are, so vague are their contents... I just know that answers A, B and C are wrong. So I vote by elemination.

C and E correct.