TN Hist288 Listing unused Historian tags
Description
This article from InSource shows how to get a list of tags that are no longer being Historized in the Wonderware Historian. This may happen as a system grows over the years and objects (and tags get renamed). This article assumes the user is using Application Server.
- Author: Lewis Talley
- Published: 03/14/2018
- Applies to: Historian + AppServer (various)
Details
I first query the GR DB for a list of all objects being historized and combine it in a format similar to how it is represented in the historian (see below)
AppServer
Agitator_005 (object) AuxContact (attribute)
Historian
Agitator_005.AuxContact
The first part of the query simply combines this in a temp table which will be used later in the query.
Then we compare the results against a query to the historian, by doing a RIGHT JOIN to return a list of tags in the Historian that do not match with object references in the GR. Basically, we produce a list that the Historian "thinks" is being historized, but in reality is not. The complete query is below:
Select Distinct (g.Tag_Name + '.' + p.Primitive_Name) as 'History TagName' into #TempTable
from Primitive_Instance p
Join gobject g
on g.gobject_id = p.gobject_id
Where p.Extension_Type = 'HistoryExtension'
and g.Is_template <> 1
select h.TagName
from #TempTable t
Right JOIN [Historian].[Runtime].[dbo].[Tag] h
on t.[History TagName] = h.Tagname
Where t.[History TagName] is null