问题
I'm using the sys.dm_tran_locks
view to check what areas of my database have locks when we are having performance problems.
Using this view....
If the resource_type is database I can use the DB_NAME function to find out what database has the lock.
If its an object I can normally join to sys.tables to check what table it is.
However if the resource_type is Page or Key is there any way to trace this back to its parent table so I can get a good idea of which tables are locking?
回答1:
This is what the resource_associated_entity_id
column is for (Example query).
SELECT dm_tran_locks.request_session_id,
dm_tran_locks.resource_database_id,
DB_NAME(dm_tran_locks.resource_database_id) AS dbname,
CASE
WHEN resource_type = 'OBJECT'
THEN OBJECT_NAME(dm_tran_locks.resource_associated_entity_id)
ELSE OBJECT_NAME(partitions.OBJECT_ID)
END AS ObjectName,
partitions.index_id,
indexes.name AS index_name,
dm_tran_locks.resource_type,
dm_tran_locks.resource_description,
dm_tran_locks.resource_associated_entity_id,
dm_tran_locks.request_mode,
dm_tran_locks.request_status
FROM sys.dm_tran_locks
LEFT JOIN sys.partitions ON partitions.hobt_id = dm_tran_locks.resource_associated_entity_id
LEFT JOIN sys.indexes ON indexes.OBJECT_ID = partitions.OBJECT_ID AND indexes.index_id = partitions.index_id
WHERE resource_associated_entity_id > 0
AND resource_database_id = DB_ID()
ORDER BY request_session_id, resource_associated_entity_id
回答2:
You've got to find the object_id associated with that resource, and it may involve joining to another table. For example,
SELECT *, OBJECT_NAME(p.object_id)
FROM sys.dm_tran_locks l
JOIN sys.partitions p
ON l.resource_associated_entity_id = p.hobt_id
WHERE resource_type = 'KEY'
Look up sys.dm_tran_locks in Books Online to figure out what the joining tables should be for each resource.
来源:https://stackoverflow.com/questions/7820907/how-to-find-out-what-table-a-page-lock-belongs-to