Trending data stored using system.tag.storeTagHistory

I’m writing to the Ignition history tables using system.tag.storeTagHistory from a gateway timer script. This seems to work OK and I can interrogate the data using system.tag.queryTagHistory.

What I can’t do is trend any of the data using an Easy Chart. Tags stored in the same history table using Tag History work, but not those stored using storeTagHistory.

Any ideas on what I’m missing?

Have you tried generating a row in tagPens by hand? It might be a drag/drop limitation.

I’ve tried that but no improvement. I also tried reading data into a standard Chart using the Tag History interface - again this shows data for the tags recorded using Tag History but not for tags recorded using storeTagHistory.

Have you done a query against the actual table in the database?
I would query a working tag and an non working tag and compare the differences between them.

SELECT [tagid]
FROM [IGN].[dbo].[sqlt_data_1_2018_04]
WHERE [tagid]=123
OR [tagid]=321

Also query against the sqlth_te table to see if there is something different between the tags in there as well.

FROM [IGN].[dbo].[sqlth_te]
WHERE [id]=123 or [id]=321
AND retired is null

Where 123 is the working tag id and 321 is the non working tagid

1 Like

There aren’t any obvious differences in the SQL tables. It looks like something internal to Ignition.

Anthony from Tech Support helped solve this one.

It turns out in both the Easy Chart and the original Chart you have to specify the fully-qualified path to the tag. This means instead of


you will have something like


In both the Easy Chart and original Chart (when using Tag History) there is a Use Fully-qualified paths option when you are choosing the tag.

1 Like