Modify a Data Store

About this task

You can change the name and description of a data store. You can also set a data store as default. In addition, you can configure the default settings of archives.

Procedure

  1. Access the Web Admin console.
  2. Select Data Stores.
    A list of data stores appears.
  3. In the Edit column, select .
    The Edit Data Store Configuration window appears.
  4. Modify values as described in the following table.
    Field Description
    Data Store Name Enter a unique name for the data store. A value is required. You can use all alphanumeric characters and special characters except / \ * ? < > |
    Note: You cannot rename the system data store.
    Description Enter a description for the data store.
    Is Default Switch the toggle on if you want to set this data store as the default one. A default data store is the one that is considered if you do not specify a data store while adding a tag. You can set only one data store as default.
  5. Select Save.
    The data store is modified.
  6. If you want to modify the default settings of archives in the data store, in the row containing the data store, select .
    The details of the data store appear.
  7. Select Configuration, and then modify values as described in the following table.
    Field Description
    Default Archive Path The default path of the folder in which you want to create the archives for the data store.
    Note: We recommend not to use a period in the default archive path field. If you do so, you will not be able to specify a default archive name.
    Base Archive Name A prefix that you want to add to all the archive files.
    Use Caching Indicates whether caching must be enabled. When reading data from the archiver, some data is saved in the system memory and retrieved using caching. This results in faster retrieval as the data is already stored in the buffer.

    This option is not available for SCADA Buffer data stores.
    Default Backup Path Not applicable. Use EFS to back up and restore archives.
    Free Space Required (MB) Indicates the remaining disk space required after a new archive is created. If the available space is less than the requirement, a new archive is not created.
    Generate Message on Data If this option is enabled, an audit log entry will be made any time the value of a previously archived data point in the Historian archive is overwritten. This log entry will contain both the original and new values.

    If you want to create multiple archives at the same time, disable this option.

    This option is not available for SCADA buffer data stores.
    Archive Duration The duration of a newly created archive in days or hours. A new archive will be created after the selected number of days or hours.
    Automatically Create Archives If enabled, the server automatically creates a new archive in the default path directory whenever the current archive is full. If disabled, no new data will be written to the archives after the current archive is full.
    Store OPC Quality Stores the OPC data quality.

    To create multiple archives at the same time, Store OPC Quality must be Disabled.
    Data Read Only After (hrs) The number of hours, prior to now, for which data can be stored in a read/write archive. After the time expires, that portion of the archive file is automatically made read-only. Incoming data values with timestamps prior to this time are rejected.

    A single archive file, therefore, may contain a read-only section, another read-write section containing recently written data, and unused free space.
    Overwrite Old Archives When enabled, the system replaces the oldest archived data with new data when the default size has been reached.
    • To create multiple archives at the same time, disable this option.
    • If you enable both Automatically Create Archives and Overwrite Old Archives, you must set ihArchiveFreeSpaceHardLimit to TRUE using APIs.
    Stale Period Specifies the duration in days after which tags are considered stale for this data store. Valid values are:
    • 0: If you enter this value, tags are never considered stale.
    • 7 to 36500 (100 years)
    Stale tags are tags that have no new data samples within a specified period of time. These tags add to system overhead and slow down user queries.
    Stale Period Check Specifies the frequency in days with which the staleness of the tag is checked. You can enter a value between 1 and 30.

    Stale tags are tags that have no new data samples within a specified period of time. These tags add to system overhead and slow down user queries.
  8. Select Update.
    The archive settings of the data store are modified.