I use this query whenever I need to investigate Maintenace Mode history for SCOM agents.
USE OperationsManagerDW SELECT ManagedEntity.DisplayName, MaintenanceModeHistory.* FROM ManagedEntity WITH (NOLOCK) INNER JOIN MaintenanceMode ON ManagedEntity.ManagedEntityRowId = MaintenanceMode.ManagedEntityRowId INNER JOIN MaintenanceModeHistory ON MaintenanceMode.MaintenanceModeRowId = MaintenanceModeHistory.MaintenanceModeRowId where DisplayName Like '%SERVERNAME%' order by ScheduledEndDateTime
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