We had couple of deadlock issues,

but nothing is captured with this query..

select XEventData.XEvent.value('(data/value)[1]', 'varchar(max)') as DeadlockGraph

FROM

(select CAST(target_data as xml) as TargetData

from sys.dm_xe_session_targets st

join sys.dm_xe_sessions s on s.address = st.event_session_address

where name = 'system_health') AS Data

CROSS APPLY TargetData.nodes ('//RingBufferTarget/event') AS XEventData (XEvent)

where XEventData.XEvent.value('@name', 'varchar(4000)') = 'xml_deadlock_report'