Handling Errors8% of the exam
Try scope error handling and transactions
Write a Try scope with its own Error Handler and predict the payload, variables and next processor after an error is continued or propagated; use a Try scope inside a subflow or a Scatter-Gather route; and choose transactionalAction INDIFFERENT, ALWAYS_BEGIN or BEGIN_OR_JOIN.
Apply correct processors /syntax to implement try scopes, and predict outcomes.
~7 min read · 4 practice questions ·
What the exam expects
- Write a
<try>scope with its own<error-handler>and predict the payload and the next processor that runs after an error inside it. - Predict whether the flow's Error Handler runs when the Try scope's handler continues or propagates, and what happens to variables set in either handler.
- Add error handling to a subflow (or a Scatter-Gather route) with a Try scope.
- Choose
transactionalAction(INDIFFERENT,ALWAYS_BEGIN,BEGIN_OR_JOIN) and state the defaults.
Key terms:
- Try scope (
<try>): wraps processors and handles their errors inline with its own Error Handler, like a separate flow without defining one. transactionalAction: whether the scope begins, joins or ignores a transaction; defaultINDIFFERENT.transactionalType:LOCAL(default) orXA, used only when the scope creates a transaction.
Key facts
After an error in a Try scope
- Detail
- Remaining components in the scope are not executed
On Error Continue in a Try scope
- Detail
- Processing continues at the next component after the scope
On Error Propagate in a Try scope
- Detail
- Error goes to the flow's Error Handler as if the Try did not exist
Payload and variable changes in handlers
- Detail
- Propagated through the rest of the execution
Try Error Handler content
- Detail
- One
<error-handler>with at least one On-Error component; first match runs
transactionalAction default- Detail
INDIFFERENT
transactionalType default- Detail
LOCAL(other valueXA)
ALWAYS_BEGIN inside an active transaction- Detail
- Raises an error
Subflow error handling
- Detail
- No built-in Error Handler; use a Try scope inside
- What happens to a Try scope's transaction when none of its operations fails?
- Why does
transactionalTypemake no difference underINDIFFERENT? - When should a Try scope use
BEGIN_OR_JOINinstead ofALWAYS_BEGIN? - What must a Try scope's Error Handler contain, and which strategy runs when several match?
The questions are free to read. Answers with their sources and self-grading are included with the pack.
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