Oracle Database Discussions

Hi,

I found the following question and do not understand the answer:

You want to use the Flashback Transaction Query to identify the SQL needed to reverse a transaction in the HR. EMPLOYEES table. Where can you find out the value of the transaction ID column XID to use when you query FLASHBACK_TRANSACTION_QUERY?

a) from the VERSIONS_XID column of HR.EMPLOYEES
b) from LogMiner
c) from XID column of HR.EMPLOYEES
d) from the VERSIONS_XID column of FLASHBACK_VERSION_QUERY

Answer A

Every table has the pseudo-column VERSIONS_XID that you can query for a transaction ID of a past transaction with the AS OF clause.

D is incorrect because there is no such column VERSIONS_XID of the FLASHBACK_VERSION_QUERY; you need to have the XID or SCN before querying FLASHBACK_VERSION_QUERY and retreive the SQL to reverse the transaction.


I think the answer is D and not A. A is a flashback query that does not show the VERSIONS_XID column. Flashback version query using VERSIONS BETWEEN shows the VERSION_XID column. Can somebody confirm this or explain please?

Thanks.