Explanation:
Box 1: join
An inner join.
This query uses kind=inner to specify an inner-join, which prevents deduplication of left side values for DeviceId.
This query uses the DeviceInfo table to check if a potentially compromised user (<account-name>) has logged on to any devices and then lists the alerts that have been triggered on those devices.
DeviceInfo
//Query for devices that the potentially compromised account has logged onto
| where LoggedOnUsers contains '<account-name>'
| distinct DeviceId
//Crosscheck devices against alert records in AlertEvidence and AlertInfo tables
| join kind=inner AlertEvidence on DeviceId
| project AlertId
//List all alerts on devices that user has logged on to
| join AlertInfo on AlertId
| project AlertId, Timestamp, Title, Severity, Category
DeviceInfo LoggedOnUsers AlertEvidence "project AlertID"
Box 2: project
Reference: https://docs.microsoft.com/en-us/microsoft-365/security/defender/advanced-hunting-query-emails- devices?view=o365-worldwide