.. _conf.dm.tools_hist.impexp:

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Import/Export Historical Data
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In the system, the values of tags at specific dates and times are stored against timestamps, forming what we refer to as a tag’s historical data. This historical data is crucial for tracking and analysing changes over time. To facilitate easy management of this data, you can import or export the historical values of tags using an Excel file. This functionality ensures that you can efficiently handle large datasets and maintain accurate records of tag values.

Export Historical Data
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To export historical data of tags, follow the steps below:

1. Choose :menuselection:`Configuration --> Data Management --> Tools --> Import/Export Historical Data` from the menu.
2. Go to the **Export Historical Data** tab.
3. Use the **Start Date** and **End Date** fields to set the required timeframe.
4. Select the tags whose historical data you want to export.

   .. tip:: You can filter tags by their name using the filtering option at the top of the **Name** column. Just enter the search term and click |filter| to execute. Click |removefilter| to remove the filter if required.


5. Click |Export| **Export Historical Data**.

   ..  admonition:: Result

       The Excel file is generated and automatically downloaded. You can open the file from your *Downloads* folder.



Import Historical Data
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When importing historical data, you upload an Excel file that contains the data you want to import. Before importing data, ensure that this Excel file has the required format so that the system can interpret the data correctly.

.. tip:: Use the |download| **Download Historical Data Template** button on the **Import Historical Data** tab to generate an Excel template in a format suitable for importing data and update it as required.

To import historical data for tags, follow the steps below:

1. Choose :menuselection:`Configuration --> Data Management --> Tools --> Import/Export Historical Data` from the menu.
2. Go to the **Import** tab.
3. Click **Choose File**, navigate to the file that you want to import and select it for import.
4. Click |import| **Import Historical Data**.

   ..  admonition:: Result

       Data from the Excel file is imported and data is updated in the system. If the tag historical values already exist for the configured timestamp, the existing value will be updated. If the tag historical values do not exist for the configured timestamp, a new historical value will be created.



.. |import| image:: images/icon.import.png
    
.. |export| image:: images/icon.export.png

.. |filter| image:: images/icon.filter.png

.. |removefilter| image:: images/icon.filter.remove.png

.. |download| image:: images/icon.download.png