Enabling Checkpoints in your SSIS
Packages
Checkpoints are a
great tool in SSIS that many developers go years without even experimenting
with. I hope to enlighten you on what Checkpoints are and why it is beneficial
to use them. Also, I will walk you through a basic example package where they
have been implemented.
What does it do?
With Checkpoints
enabled on a package it will save the state of the package as it moves through
each step or task and place it in a XML file upon failure of the package. If
your package does fail you can correct the problem in your package and rerun
from the point of the tasks that did not successfully run the first time. Once
the package completes successfully the file is no longer needed and
automatically discarded.
How does this benefit you?
Just imagine your
package is loading a table with 10 million records. Your package passes the
Data Flow that performs this huge load without any problem (Other than the fact
that it took two hours to load). The next task in your package is a Send Mail
Task and for some reason fails.
You correct the
problem in the Send Mail Task, but without using Checkpoints your package would
still have to run that Data Flow that loads the 10 million records again
(taking another two hours) even though you’ve already done it once. If you had
enable Checkpoints on this package you could simply correct the problem in the
Send Mail Task and then run the package again starting at the Send Mail Task.
Sounds great right?
How do I configure it?
This example will run
you through very basic package using Checkpoints.
Example Overview
- Use Three Execute SQL
Task using the AdventureWorks2009 (It can really be any database for this
example) database as a connection manager.
- Configure the package to
handle Checkpoints
- Configure the individual
tasks to handle Checkpoints
Step 1: Configure Execute SQL Tasks
- Drag three Execute SQL
Tasks on your Control Flow.
- Use any database for the
Connection property on all three tasks
- Configure Execute SQL
Task SQLStatement property: Select 1
- Configure Execute SQL
Task 1 SQLStatement property: Select A (Set to intentionally fail)
- Configure Execute SQL
Task 2 SQLStatement property: Select 1
Step 2: Configure Package to enable Checkpoints
- Open the properties menu
at the package level
(Just open properties in the Control Flow without any task or connection
manager selected)
- Change the properties
CheckpointFileName: c:\Checkpoint.xml
(Feel free to use the .txt extension when naming the
checkpoint if you want to open it in notepad and look at it!)
- Change the properties
CheckpointUsage: IfExists
- Change the properties
SaveCheckpoints: True
Step 3: Configure Each Task
- Select each task
individually and open the properties menu at the task level (Just click the
task once then hit F4)
- Change the
FailPackageOnFailure property to True
Step 4: Run the Package
- Run the package and you
will see the package fail on the second task
- This also created the
file c:\Checkpoints.xml. Feel free to open it and take a look! I use the
tool XML Notepad to view XML Files. It’s Free.
- You could also save this
file with the.txt extension and just view in regular notepad and it still
works as a Checkpoint.
• If you run the package a second time it will skip the first
task that was successful and start right at the second task
Step 5: Correct the Problem and Rerun Package
- Open the Execute SQL
Task 2 and configure the SQLStatement property: Select 1
- The package has now
completed and skipped the first step which already succeeded. Imagine if
that first step would normally take two hours to run!
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