openHistorian measurements table

[maria]

Hello, I am currently working with openHistorian for the first time. I’ve managed to configure openHistorian with PostgresSQL and I imported a PMU device to read some measurements.

My problem is that I want to create an API to get the values of the measurements from the DB but I cannot find the measurements from the PMU device that I can see in the Trends data of openHistorian website in the PostgresSQL database.

Where are the measurements stored?

[StephenCWills]

Measurements are stored in archive files that exist in the working directory as *.d2i files and in the archive directory as *.d2 files. By default, these two directories point to the same location, which is the Archive folder in the openHistorian installation directory. For some more in-depth information on where data is stored, the following post in the section titled The openHistorian file format describes the various stages the data will go through as it’s written to the historian.

OpenHistorian Archive file reading/writing programmatically

I’m struggling to read through your post to understand all the questions you have so I’m just going to focus on two major points. Data gap recovery The recommended solution to this problem does not rely on the PMU to capture its own data while the connection is down, but rather to set up another system with enough storage to support a short-term archive of local PMU data. This system handles the buffering of data in the short-term archive and also providing data to the central openHistorian. T…

[maria]

Thank you for your answer! My question is about the PostgresSQL DB. In which table are the measurements stored?

[StephenCWills]

By default, measurements are stored in the openHistorian archive files, not the PostgreSQL database. The only way to configure the system to write to an RDBMS would be to set up an ADO Output Adapter or else create your own custom adapter.