What is Precedence Constraint

 Precedence constraints are the green, red, and grey connectors in the Control Flow that link the tasks together and can be used to manage the workflow of a package and handle error conditions.

Precedence Constraint Basics

The main purpose of precedence constraints is to control when tasks and containers should run in relation to one another. This revolves around whether tasks succeed (green), fail (red), or just complete with either a success or a failure (grey). Precedence constraints can also be more granularly controlled through advanced properties, which are addressed in the next section.


Precedence Constraint is used for enabling the developers to define a set of tasks logically and define the order of execution. These are connectors used for connecting all the tasks.




A task will only execute if the condition that is set by the precedence constraint preceding the task is met.  By using these constraints, it will choose different execution paths depending on the success or failure of other tasks.

  • Success: Workflow will proceed when the preceding container executes successfully. Indicated in control flow by a solid green line.

  • Failure: Workflow will proceed when the preceding container’s execution results in a failure. Indicated in control flow by a solid red line.

  • Completion: Workflow will proceed when the preceding container’s execution completes, regardless of success or failure. Indicated in control flow by a solid blue line.

  • Expression/Constraint with logical AND: workflow will proceed when specified expression and constraints evaluate to true. Indicated in control flow by a solid color line along with a small ‘fx’ icon next to it. Color of line depends on logical constraint chosen (e.g. success = green, completion = blue).

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