Tag history binding to table on multiple tags provides multiple rows for each timestamp

General Discussion
1

Hi,

I have an issue while trying to make a neat table that provides data of historical tags (updated through Tag History binding). Even though the three tags are being written at the same time, there is a timestamp (row in table) for each separate change… resulting in 3 times more rows than necessary… redundant and confusing. It would be nice just to see all the values after each tag is written.

In the tables below, the top table has 3 ‘Selected Historical Tags’, while the lower tables have only one tag each. I’d like the data from the bottom 3 tables to be summarized in one table.

These tags are part of the same UDT and set to a historical scan class of ‘Evaluate On Change’.

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Is there an easy way to prevent getting 3 timestamps each time I write to these tags? I tried system.tag.writeAllSynchronous but this still creates a new row for each tag change. Is it necessary to look into scripting a dataset that groups data with the same timestamp?

Thanks!

Michael

2

Check this link: How to query history

3

Thank you. I set it up as a Transaction Group and it seems to be doing what I need. Haven’t done much with transaction groups myself but it seems like a better way to store batch data.

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