A correlation rule is created to detect potential insider threats by correlating user login events...

In Cortex XDR, correlation rules useXQL (XDR Query Language)to combine data from multiple datasets to detect patterns, such as insider threats. Thejoinoperation in XQL is used to correlate events from two datasets based on a common field (e.g., user ID). The type of join determines how records are matched and retained when there are no corresponding events in one of the datasets.

The question specifies that the correlation rule must retainall user login eventsfrom dataset x (the primary dataset containing login events), even if there are no matching file access events in dataset y (the secondary dataset). This requirement aligns with aLeft Join(also called Left Outer Join), which includes all records from the left dataset (dataset x) and any matching records from the right dataset (dataset y). If there is no match in dataset y, the result includes null values for dataset y’s fields, ensuring no login events are excluded.

Correct Answer Analysis (B):ALeft Joinensures that all records from dataset x (user login events) are retained, regardless of whether there are matching file access events in dataset y. This meets the requirement to ensure no login activity is missed.

Why not the other options?

A. Inner: An Inner Join only includes records where there is a match in both datasets (x and y). This would exclude login events from dataset x that have no corresponding file access events in dataset y, which violates the requirement.

C. Right: A Right Join includes all records from dataset y (file access events) and only matching records from dataset x. This would prioritize file access events, potentially excluding login events with no matches, which is not desired.

D. Outer: A Full Outer Join includes all records from both datasets, with nulls in places where there is no match. While this retains all login events, it also includes unmatched file access events from dataset y, which is unnecessary for the stated requirement of focusing on login events.

Exact Extract or Reference:

TheCortex XDR Documentation Portalin theXQL Reference Guideexplains join operations: “A Left Join returns all records from the left dataset and matching records from the right dataset. If there is no match, null values are returned for the right dataset’s fields” (paraphrased from the XQL Join section). TheEDU-262: Cortex XDR Investigation and Responsecourse covers correlation rules and XQL, noting that “Left Joins are used in correlation rules to ensure all events from the primary dataset are retained, even without matches in the secondary dataset” (paraphrased from course materials). ThePalo Alto Networks Certified XDR Engineer datasheetlists “detection engineering” as a key exam topic, including creating correlation rules with XQL.