It is recommended to run tests on the draft pipeline before publishing to ensure the pipeline is working as expected. Live tests allow running pipeline end to end. It has 2 modes - Run by date range OR Run by external id. This article provides details on both modes.
By Date / Time Range (Updated At)
Use this mode if you want to run a live test on set of records modified in a given time range. This is recommended when you want multiple records (larger sample set) to be run through testing. When this mode is selected, the pipeline pulls all records that were updated within selected start and end time range. You can specify the limit if you do not want all records to be pulled. In this mode, all sources will be queried for data.
Once the test is started, the sync cycle is kicked off. The draft cannot be modified and is locked until the test completes.
When the test processing is completed, you will see the results. The right panel shows the number of records processed and status of different stages in the pipeline. Clicking on each stage shows the input and output for each field in the bottom panel.
If you navigate out of the sync studio page before the test completes, no need to worry. There is a notification sent to your in-app inbox once the test is complete and you can see the results in the Tests -> Live Test Results menu option on the draft.
The test logs record level transactions like the incremental sync. To learn more about Logs, see Using Transactions.
By External ID
Use this mode if you want to run a live test on set of records for known external ids. You can specify the external id for each source synapse entity in the pipeline. Use comma separated values when specifying multiple ids. You can control the sources to run by selecting the synapse of choice if you do not wish to query all sources. Once the test is started, the execution, results and notification are exactly same as the previous mode.
There are some synapses that do not support fetching records by id (example Amplitude. All Synapses have a summary help link to give you this information). For such cases, depending on the synapse, the live test fails with an error.
Cancel test
Once the test is started, there is no way to cancel it currently. This is a planned feature on the roadmap.