Appboard/2.4/builder/data collections: Difference between revisions

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|While the client can request data as frequently as it wants the server may respond with new data or cached data, or sometimes an error condition:
|While the client can request data as frequently as it wants the server may respond with new data or cached data, or sometimes an error condition:
* ''(blank)'': no status available
* ''(blank)'': no status available
* ''fresh'': server responded with new data (less than 5 seconds old)
* ''cached (n seconds old)'': The server returned cached data which is ''n'' seconds old. If cached data is returned this indicates the data source is configured to cache results - see the data source configuration for the actual cacheTimeout (maximum cache age). Also see the [[appboard/2.4/builder/caching_and_polling|Caching and Polling]] page for more information.]]
* ''expired (n seconds ago)'': The server returned stale data on purpose, most likely because there was cached data but there was an issue with the data source when fetching new data.
|-
|-
|''Status''
|''Status''

Revision as of 09:42, 2 October 2013

HeaderFlow03.png

Data Collections are sets of tabular data that are maintained in memory by AppBoard. The contents of the Data Collections can be manipulated through filtering, grouping, sorting and pivoting features available in the Data Collections Wizard. Associations can also be established between collections to support the visualization of multiple data sets.



Reviewing Data Collections

Use these instructions to view a list of all Data Collections that are available in the system:

Field Description
Name The name of this data collection. By default data collections are created for each unique data source entity discovered in the format data_source_name.entity. These can be renamed and new data sources created however.
Rows The number of rows in the data collection. This may show zero if the data collection has never been previewed, or not currently being used (i.e. configured on a visible widget).
Data Source The name of the data source entity associated to this data collection.
Polling Period When a data collection is active, i.e. configured on a visible widget, the polling period determines how frequently the client requests for updates. By default the polling period is set to zero (Disabled). See the Caching and Polling page for more information.]]
Last Poll This is the last time the client requested the data collection. It could be from previewing the data collection, or because of a visible widget configured to use this data collection. For active data collections with polling enabled this should count up to the polling period and reset indicating the client requested new data.
Server Response While the client can request data as frequently as it wants the server may respond with new data or cached data, or sometimes an error condition:
  • (blank): no status available
  • fresh: server responded with new data (less than 5 seconds old)
  • cached (n seconds old): The server returned cached data which is n seconds old. If cached data is returned this indicates the data source is configured to cache results - see the data source configuration for the actual cacheTimeout (maximum cache age). Also see the Caching and Polling page for more information.]]
  • expired (n seconds ago): The server returned stale data on purpose, most likely because there was cached data but there was an issue with the data source when fetching new data.
Status
Preview
  1. Click "Data Collections" in the left side tool pallette.
  2. Data Collections are listed in a data grid in the first page.
  3. Each row in the data grid conveys the following details:
    • Name: the name of the Data Collection
    • Rows: Number of Rows contained in the Data Collection
    • Data Source: the Data Source associated with this Data Collection
    • Polling Period: the period of time between each re-request of the Data Collection via the data source.
    • Last Poll: the number of seconds since the last time the Data Collection was retrieved.
    • Server Response: conveys the status associated with the most recent server response. This column will contain:
      • blank: No status available.
      • fresh: The server fetched the data from the data source within the last 5 seconds.
      • cached (n seconds old): The server returned cached data which is n seconds old. If cached data is returned this indicates the data source is configured to cache results - see the data source configuration for the actual cacheTimeout (maximum cache age).
      • expired (n seconds ago): The server returned cache data that was older than the configured cacheTimeout. This shouldn't happen unless the data source stopped responding and the server already had cached data.
    • Status: conveys the current status of the data collection. This status is directly tied to the health of the Data Source. The following may be displayed:
      • Green Check: the Data Collection was healthy the last time it was accessed.
      • Gray Check: there is no known problem with the data collection, but no status is available (i.e., the data collection has most likely never been accessed).
      • Yellow '!': there is a problem associated with the Data Collection as the Data Source encountered an error in the data retrieval. There will likely be log messages associated with this error on the server.
      • Red 'X': the Data Collection is not available, as the Data Source that it was associated with has been deleted.
    • Preview: to preview the data in a Data Collection, click the blue preview button in the rightmost column.

Filtering Data Collections

For general information about the various options for filtering Data Collections in AppBoard, see Filtering Data Collections.


Adding a Data Collection

Use these instructions to create a new Data Collection:

  1. Click Data Collections link in the left side tool palette.
  2. Click Add button at the bottom of the page to launch the Data Collections Wizard.
  3. On the Configure panel, enter the following:
    • Data Collection Name - Provide a unique name for the Data Collection.
    • Data Source - Select the Data Source that will be used for the Data Collection.
    • Options - Check one or more of the following options:
      1. Filter - Provides an interface for adding server-side filters to the Data Collection (See Server-Side Filters and Simple Property Comparison for more information).
      2. Server Side Sort - Allows you to specify the default sort order in which the Data Collection is displayed using these options:
        • Server Side Sort - Select the field from the Data Source by which the Data Collection will be sorted. You can select multiple columns to use for sorting.
        • Order (the box to the right) - Select either Ascending or Descending.
      3. Limit Row Count - Allows you to limit the number of rows returned by the server for this Data Collection, using the Server Side Row Limit box.
      4. Polling - Provides the option of setting a Polling Interval. This is the number of seconds to wait before the client will fetch the latest data from the server cache. For example, if this is set to 30, every 30 seconds AppBoard will refresh the Data Collection to have the latest data from the server. The minimum polling interval value is 5 seconds and the maximum value is 3600 seconds (one hour). Note: To maximize performance, Data Collections are only polled when one or more of the Widgets that uses that Data Collection is in the foreground display.
    • Click the Next button.
  4. On the Client Side Filter panel, add one or more Client Side Filter Rules as needed (See Client-Side Filters for more information).
  5. Click "Finish" to create the Data Collection.


Editing a Data Collection

Use these instructions to modify an existing Data Collection:

  1. Click Data Collections in the left side tool palette.
  2. Select the Data Collection from the data grid.
  3. Click Edit at the bottom to enter the Data Collections Wizard for that Data Collection.
  4. Make any necessary modifications to options in the Configure section.
  5. Click Next
  6. Make any necessary modifications to the Client Side Filter section.
  7. Click Finish to save the changes to the Data Collection.


Removing a Data Collection

Use these instructions to remove an existing Data Collection:

  1. Click Data Collections in the left side tool palette.
  2. Click on the Data Collection you would like to delete.
  3. Click the Delete button at the bottom of the page.
  4. Click Yes to confirm the removal of the Data Collection.