The Workflow and String Variable Limits in SharePoint
Microsoft's SharePoint provides the foundation of document management systems and online searchable databases. A SharePoint workflow controls the life cycle of the document, generates user tasks and sends notifications as items are created and modified. SharePoint string variables set limits on user queries and workflow behavior.
SharePoint Versions and Their Workflows
SharePoint 2007 only offered list workflows. SharePoint 2010 introduced site workflows that are triggered manually or by scheduled transactions. Using Microsoft SharePoint Designer lets users create workflows without needing to know how to write software code.
SharePoint Designer workflows do not have state-based execution flows such as notifications sent when a document is promoted or released. Microsoft Visio handles complex workflows with thousands of paths that can be imported into SharePoint as long as they all have a termination point. The termination point is a point where the workflow and its associated processes end.
Variables That Control Workflows
String variable limits manage and control workflows. Adding time limits to workflow tasks prevents workflows from hanging while waiting for users to complete an activity. The workflow can be designed to reassign or terminate a task if not completed in time.
Requiring a minimum number of signatures or feedback entries to a workflow ensures that documents are properly reviewed before approval. If the minimum number of approvals is not met, the workflow is cancelled. Adding a variable that terminates the workflow after a specified number of loops prevents endlessly repeating workflows.
List workflows track document approvals and recording digital signatures, commonly used in capturing signatures on contracts and approvals for financial transactions. List workflows track the life-cycle state of an item as it is created, reviewed and updated but not when deleted. SharePoint workflows do not have built-in loops.
Site workflows are triggered manually by the user or executed code such as periodic database updates. SharePoint workflows are limited to the list from which they were created.
List workflows are only triggered when an object is created or updated, not deleted. Site workflows are triggered manually by the user or executed code such as periodic database updates. SharePoint workflows operate in sequence or in parallel on one item at a time. Secondary workflows allow workflows to run in parallel with the primary workflow. Secondary workflows handle exceptions such as rejected proposals sent back to the creator for revision.
Controlling SharePoint Queries
Limiting the number of returned records to a query conserves system resources, preventing a few heavy users from consuming most of a database’s processing power and maximizing the number of users who can search SharePoint simultaneously.
The SPQuery variable contains the maximum number of items retrieved in a query. This value typically ranges from 100 to 2000, though it can be higher.
A common SPQuery variable value is 1000. SPSiteDataQuery sets the limit for queries against multiple lists and across multiple databases. Browsers limit the length of query strings. When a workflow ends by returning users to their staring webpage, the starting page URL is entered the source for the query string variable.