Work with Data Stores

Configure Data Stores

A data store is logical collection of tags used to store, organize, and manage tags according to the data source and storage requirements. A data store can have multiple archive files (*.IHA), and includes both logical and physical storage definitions.

Tags can be segregated into separate archives through the use of data stores. The primary use of data stores is to segregate tags by data collection intervals. For example, you can put a name plate or static tags where the value rarely changes into one data store, and your process tags into another data store. This can improve query performance.

Historian Data stores are stored archive files that contain data gathered from all data sources during a specific period of time. You can write and read data from the archives available under the data stores. Using data stores, you can store, organize, and manage tags according to the data source and storage requirements.

You can define two types of data stores:
  • Historical Data Store: Tags stored under historical data store will store data as long as disk space is available. Depending on your license, you may be able to create multiple historical data stores. The maximum number of Historical data stores supported depends on the license.
  • SCADA Buffer Data Store: Tags stored under the SCADA buffer data store will store data for a specific duration of time based on license.
When you install Historian 6.0 or greater, two historical data stores are installed by default.
  • System: Stores Historian messages and performance tags. This is only for internal usage within Historian, and you cannot add tags to this data store. You cannot rename or delete the System data store.
  • User: Stores the data for the tags. This is a default data store. You can rename and delete a user data store as long as there is another default data store set for tag addition.
Based on your license, a SCADA Buffer data store may also be installed.
  • SCADA Buffer: Stores short term tags and data in a SCADA Historian data store.

Moving Tags Between Data Stores

About this task

You can move tags from one data store to another. After a tag is moved, the incoming data is stored in the new data store.

When you move a tag, only the tag itself is moved; the data already associated with that tag does not automatically move with it. Moving the old data is optional, but if the old data is not moved to the new data store, it cannot be retrieved.

Procedure

  1. In the Tags page, select a single tag or multiple tags.
  2. In the Tag Editor section, select Advanced.
  3. Select Data Store to select the tag's new data store.
    A message appears asking you to confirm the change.
  4. Select Yes.
  5. Select Update.
    A message appears confirming that the tag's data store has changed and reminding you that the data has to be manually moved using MigrateIHA.exe.

What to do next

(optional) Move the data associated with the tags you just moved with the migration utility tool (MigrateIHA.exe). If you moved multiple tags, you can move the data for all, some, or none of the tags.

Before moving any data, best practice is to back up the archive file(s) that contain the old data.

Note: When migrating tags using MigrateIHA.exe, ensure that you select the Migrate using the tag mask option and specify the tag name or wildcard mask to migrate the tag you want to include. Refer to the How to use the IHA Migration Tool section in Important Product Information.

Adding a Data Store

About this task

The number of data stores you can create depends on your license.

Procedure

  1. In the Data Store Name field, enter the name of the data store.
    The following special characters cannot be used in data store names: / \ * ? < > |
  2. In the Description field, enter the description of the data store.
  3. To set this new data store as the default data store for adding tags, enable the Is Default option.
  4. Select to add the data store.
    A message appears indicating that the data store has been added.

What to do next

When you add the tags to the new data store, it will have its own set of .IHA (iHistorian Archive) files. Ensure that you back up the new data store archives periodically.

Deleting a Data Store

About this task

You can delete a data store if it is no longer needed. You cannot delete the System data store. You cannot delete the last User store; at least one User store must exist.

Procedure

  1. If there are tags assigned to the data store, reassign them to other data stores or delete them.
  2. In the Data Stores page, select the unwanted data store and then select Delete.
    A message appears asking you to confirm deletion
  3. Select OK to delete the data store.

Editing a Data Store

About this task

The following special characters cannot be used in data store file names: / \ * ? < > |

Procedure

  1. Select the Edit button.
    The Edit Data Store Configuration window appears.
  2. Make the desired change(s):
    1. To rename the data store, enter the new name in the Data Store New Name field.
    2. Enter or modify the Description.
    3. Toggle the Is Default option.
  3. Select Save to save the changes.