Verify Target

The verify target is used to execute a set of assertions after all targets have been built. This can be used to verify the results to ensure that all processing was correct. In most cases it is advisable to use the similar validate build target, which is executed in advance of the CREATE and BUILD phase and can be used to validate any assumptions on the incoming data.


    kind: verify
    mode: failNever
        kind: sql
          - query: "SELECT id,count(*) FROM output_table GROUP BY id HAVING count(*) > 0"
            expected: []
          - query: "SELECT id,count(*) FROM output_cube GROUP BY id HAVING count(*) > 0"
            expected: []
        kind: sql
        query: "SELECT COUNT(*) FROM measurements_extracted"
        expected: 2


  • kind (mandatory) (type: string): verify
  • description (optional) (type: string): Optional descriptive text of the build target
  • assertions (optional) (type: map:assertion): Map of assertions to be executed. The verification is marked as failed if a single assertion fails.
  • mode (mandatory) (type: string) (default: failAtEnd): Specify how to proceed in case individual assertions fail. Possible values are failFast, failAtEnd and failNever

Supported Execution Phases

  • VERIDY - The specified assertions will be run in the VERIFY phase after the CREATE and BUILD phases.

Read more about execution phases.


This build target works very similar to the validate target, except that it is only active during the VERIFY phase and the default for the mode parameter is set to failAtEnd. Here the assumption is that a verification should check postconditions implied by the logic of your Flowman project. Flowman should return an error in this case, but since the fault is on your side, you want to see all failed checks and not only the first one.