sp_MStrypurgingoldsnapshotdeliveryprogress (Transact-SQL MetaData) Definition

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The meta data is from an SQL 2012 Server.

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Definition:

sys.sp_MStrypurgingoldsnapshotdeliveryprogress()

MetaData:

 --   
--  Name: sp_MStrypurgingoldsnapshotdeliveryprogress  
--   
--  Description: This function removes snapshot sessions in   
--               MSsnapshotdeliveryprogress containing progress tokens that  
--               are too old (3 days or older) provided that it can acquire the   
--               'snapshot_delivery_in_progress_' + db_name() application lock  
--               in exclusive mode immediately. This is to ensure that the   
--               the removal of progress tokens will not disrupt any on-going  
--               snapshot delivery processes.  
--   
--  Parameter: none  
--   
--  Notes: This procedure is normally invoked by the distribution/merge agent  
--         at the begining of a snapshot delivery session although the database  
--         adminstrator can invoke this procedure to actively purge old entries  
--         in sp_MSsnapshotdeliveryprogress. Since this procedure  
--         is meant to provide a best-effort mechanism for cleaning up old   
--         sessions in MSsnapshotdeliveryprogress, it will not raise an error  
--         if it fails to acquire the 'snapshot_in_progress_' + db_name()   
--         application lock.  
--   
--  Returns: 0 - succeeded  
--           1 - failed  
--   
--  Security: Execute permission of this procedure is granted to public;  
--            procedural security check will be performed to make sure  
--            that the caller is either a db_owner of the current database  
--            or a sysadmin.   
--   
create procedure sys.sp_MStrypurgingoldsnapshotdeliveryprogress  
as  
begin  
    set nocount on  
    declare @retcode int  
    declare @resource nvarchar(255)  
    declare @lock_acquired int   
    declare @cursor_allocated bit  
    declare @cursor_opened bit  
    declare @pubidprefix nvarchar(100)      
    declare @pubid uniqueidentifier  
    declare @cutofftime datetime  
    select @retcode = 0  
  
    select @cutofftime = datediff(day, 3, getdate())  
    if @@error<>0 or @retcode<>0 begin select @retcode=1 goto Failure end  
  
    select @lock_acquired = 0  
    exec @retcode = sys.sp_MSreplcheck_subscribe   
    if @retcode <> 0 or @@error <> 0  
    begin  
        select @retcode = 1  
        goto Failure  
    end  
  
    select @resource = 'snapshot_delivery_in_progress_' +   
        db_name() collate database_default  
    select @cursor_allocated = 0  
    select @cursor_opened = 0  
    select @pubidprefix = N'<MergePubId>:'  
  
    exec @retcode = sys.sp_getapplock @Resource = @resource,  
                                      @LockMode = 'Exclusive',  
                                      @LockOwner = 'Session',  
                                      @LockTimeout = 0,  
                                      @DbPrincipal = N'db_owner'  
    --  Bail on critical errors from sp_getapplock  
    if @retcode < -1 or @@error <> 0  
    begin  
        select @retcode = 1  
        goto Failure  
    end  
  
    --  Lock request timeout because a snapshot is being delivered; bail  
    --  without raising an error  
    if @retcode = -1  
    begin  
        select @retcode = 0  
        goto Failure  
    end  
    select @retcode = 0  
    select @lock_acquired = 1  
  
    --  Delete all sessions containing tokens that are more than 3 days old  
    if object_id('dbo.MSsnapshotdeliveryprogress') is not null  
    begin  
        --  Eliminating merge snapshot progress requires additional cleanup in  
        --  the merge meta-data tables so do it separately  
        declare hpubid cursor local fast_forward for   
            select convert(uniqueidentifier, right(progress_token, len(progress_token) - len(@pubidprefix)))   
              from dbo.MSsnapshotdeliveryprogress  
             where left(progress_token, len(@pubidprefix)) = @pubidprefix  
               and session_token in  
                    (select session_token  
                       from dbo.MSsnapshotdeliveryprogress sdp_inner  
                      where progress_timestamp < @cutofftime)  
        if @@error<>0 or @retcode<>0 begin select @retcode=1 goto Failure end  
        select @cursor_allocated = 1      
  
        open hpubid  
        if @@error<>0 or @retcode<>0 begin select @retcode=1 goto Failure end  
        select @cursor_opened = 1      
          
        fetch hpubid into @pubid  
        while (@@fetch_status <> -1)  
        begin  
  
            exec @retcode = sys.sp_MSpurgepartialmergesnapshot  
                    @pubid = @pubid  
            if @@error<>0 or @retcode<>0 begin select @retcode=1 goto Failure end  
            fetch hpubid into @pubid  
        end  
  
        close hpubid   
        if @@error<>0 or @retcode<>0 begin select @retcode=1 goto Failure end  
        select @cursor_opened = 0  
     
        deallocate hpubid  
        if @@error<>0 or @retcode<>0 begin select @retcode=1 goto Failure end  
        select @cursor_allocated = 0  
  
        delete dbo.MSsnapshotdeliveryprogress  
        where session_token in   
            (select session_token  
               from dbo.MSsnapshotdeliveryprogress sdp_inner  
              where progress_timestamp < @cutofftime)  
        if @@error <> 0  
        begin  
            select @retcode = 1  
            goto Failure  
        end  
    end  
      
Failure:  
    if @cursor_opened = 1  
    begin  
        close hpubid  
    end  
      
    if @cursor_allocated = 1  
    begin  
        deallocate hpubid  
    end  
  
    if @lock_acquired = 1  
    begin  
        exec @retcode = sys.sp_releaseapplock @Resource = @resource,  
                                              @LockOwner = 'Session',  
                                              @DbPrincipal = N'db_owner'  
  
        if @retcode < 0 or @@error <> 0  
        begin  
            select @retcode = 1  
        end  
    end  
    return @retcode              
end