Finding locks on the table and all locking queries:

        sys.dm_tran_locks Metadata table contains the sessions which are currently locking a resource or waiting for a lock.

Finding if a table is locked :

you can filter on resource_associated_entity_id  with object id. 

SELECT 

* 

from 

sys.dm_tran_locks 

where 

DB_NAME(resource_database_id) = 'dbname' 

and resource_associated_entity_id = object_id('schemaname.tablename')

Finding all locking Queries

sys.dm_exec_requests contains exec requests on the server. It contains the "sql_handle" you can pass it to "sys.dm_exec_sql_text" table values function to get the text corresponding to the handle.

SELECT 
         (select text from sys.dm_exec_sql_text(exrequests.sql_handle))
from
sys.dm_tran_locks dbl
INNER JOIN  sys.dm_exec_requests exrequests on dbl.request_session_id = exrequests.session_i
where
DB_NAME(dbl.resource_database_id) = 'dbname'

Finding the login name of the user:

sys.dm_exec_sessions contains login information of the session.

SELECT
DB_NAME(resource_database_id)
, s.original_login_name
, s.status
, s.program_name
, s.host_name
, (select text from sys.dm_exec_sql_text(exrequests.sql_handle))
,*
from
sys.dm_tran_locks dbl
     JOIN sys.dm_exec_sessions s ON dbl.request_session_id = s.session_id
INNER JOIN  sys.dm_exec_requests exrequests on dbl.request_session_id = exrequests.session_id
where
DB_NAME(dbl.resource_database_id) = 'dbname'

Thanks for reading. Please let me know if there is any more info needed.

DML Operations on Views

Simple views:

     Views with simple select statements are updatable with normal DML statements. More precisely If the database system can determine the reverse mapping from the view schema to the schema of the underlying base tables, then the view is updatable. 

Example:

You can see actual underlying table is updated.

Read Only Views:

If DBMS cannot map the changes to the underlying base tables. 

The views with following clause in the select statements are readonly

1. Group by
2. Distinct
3. aggregates 
4. pivot
5. unpivot

We can use instead of triggers to update these views.

Instead Of Trigger:

Instead Of Insert trigger can be used to perform the operations when there is an insert performaed on the view. Example, we can insert the data into the underlying table when there is an insert performed on the view. 

Example

CREATE TRIGGER [InsteadTrigger_Name] on TestView
INSTEAD OF INSERT
AS
BEGIN

  INSERT INTO [Raghu].[dbo].[Test]
       SELECT Color, Material
       FROM inserted
END;
GO

Please feel free to comment if you need any other information, Or you want to add more.