blocking query and header blocker query in sqlserver

 To check blocking

select * from sys.sysprocesses where blocked <> 0

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head blocker

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declare @handle binary(20), @spid int

select top 1 @spid = blocked

from master..sysprocesses a

where a.blocked != 0 

and a.blocked not in (select spid from master..sysprocesses b where blocked != 0)

if @spid is not null

begin

  select @handle = sql_handle from master..sysprocesses where spid = @spid

  exec sp_who2 @spid

  dbcc inputbuffer (@spid)

select lastwaittype from sysprocesses where spid=@spid

  select * from ::fn_get_sql(@handle)

end