User-Provided Control Functions
At a minimum, each customized operator must define the following user-provided control functions:
Function |
Use |
Preparing the operating environment for executing operators by performing the following tasks: |
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Performing the following data access and manipulation tasks: |
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Writing checkpoint records to a restart log table that the operator can use to restart in case of a hardware or software system failure. |
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Restarting operators using the most recently written checkpoint records. |
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Performing event processing or notification based on caller-specified event. |
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Releasing system resources allocated by the corresponding Initiate function. |