Difference between revisions of "Presence Context"

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(Data Table)
(Data Table)
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===Data Table===
 
===Data Table===
  
In Presence, data is stored in a virtual table consisting of rows and columns. This is populated by querying databases, XML documents, Web Services, mail accounts etc, or via the [[Create Data Table]] Node. Only one Data Table exists at any time. Joining queries together causes the Data Table to be appended with new results. A full list of Task Elements that populate the Data Table can be found in the [[Task Elements#Data Access]] section.
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In Presence, data is stored in a virtual table consisting of rows and columns. This is populated by querying databases, XML documents, Web Services, mail accounts etc, or via the [[Create Data Table]] Node. Only one Data Table exists at any time. Joining queries together causes the Data Table to be appended with new results. A full list of Task Elements that populate the Data Table can be found in the [[Task Elements#Data Access|Data Access Task Elements]] section.
  
 
=== Local and Task Variables ===
 
=== Local and Task Variables ===

Revision as of 13:02, 28 January 2011

The Presence Context

http://www.international-presence.com/wikidocs/images/presence_context.png


What is the Presence Context?

The Presence Context is a container which is retained in memory and is passed from node to node during a Task execution. It contains information such as:

  • The current Data Table
  • Local Variables
  • Internal information about the current task and the container that it is running in

Data Table

In Presence, data is stored in a virtual table consisting of rows and columns. This is populated by querying databases, XML documents, Web Services, mail accounts etc, or via the Create Data Table Node. Only one Data Table exists at any time. Joining queries together causes the Data Table to be appended with new results. A full list of Task Elements that populate the Data Table can be found in the Data Access Task Elements section.

Local and Task Variables

This is a collection of name / value pairs. See the section on Variables for a more detailed explanation. Please note that until a Global Variable is committed (when a Task completes successfully) it is treated as a Task Variable within the Presence Context.

Saving and Loading

The Presence Context can be saved as an XML document mid-Task. This can be helpful for debugging your Tasks, or when obtaining support from International Presence. Please see Context XML Nodes for further information.