Check for active preview sessions in SDL Tridion 2013 SP1 MS SQL database
SELECT TOP 100 [PREVIEW_SESSION_ID]
,[EXPIRATION_DATE]
FROM [SessionPreview].[dbo].[PREVIEW_SESSIONS];
SELECT TOP 100 [ITEM_REFERENCE_ID]
,[PUBLICATION_ID]
,[FILENAME]
,[URL]
,[TEMPLATE_ID]
FROM [SessionPreview].[dbo].[PAGE];
SELECT TOP 100 [ITEM_REFERENCE_ID]
,[PUBLICATION_ID]
,[SCHEMA_ID]
,[IS_MULTIMEDIA]
FROM [SessionPreview].[dbo].[COMPONENT];