2.8.6 PrecedenceConstraintType

The PrecedenceConstraintType complex type is used to specify an object that contains precedence constraints between the executable elements within a package.

The following is the XSD of the PrecedenceConstraintType complex type.

   <xs:complexType name="PrecedenceConstraintType">
     <xs:sequence>
       <xs:element name="Property"
                   maxOccurs="unbounded">
         <xs:complexType>
           <xs:complexContent>
             <xs:extension base="DTS:PropertyElementBaseType">
               <xs:attribute name="Name"
                   type="DTS:PrecedenceConstraintPropertyNameEnum"
                   use="required"/>
             </xs:extension>
           </xs:complexContent>
         </xs:complexType>
       </xs:element>
       <xs:element name="PropertyExpression"
                   type="DTS:PropertyExpressionElementType"
                   minOccurs="0" maxOccurs="unbounded"/>
       <xs:element name="Executable"
                   type="DTS:PrecedenceConstraintExecutableReferenceType"
                   minOccurs="1" maxOccurs="unbounded"/>
     </xs:sequence>
   </xs:complexType>

The following table provides additional information about the elements, types, and constraints for the PrecedenceConstraintType complex type.

Element	Additional constraints	Type definition	Description
Property	In some cases, constraints are placed on the Property element’s value for specific values of the Name attribute of the Property element. If such constraints exist, they are specified where the meaning of the particular property name is specified. These constraints MUST be followed. If the optional DataType attribute is present, the value of the Property element MUST be of the type that is indicated by the DataType attribute.	Inline in the XSD in this section.	Property elements contain values for many different properties associated with an instance of the containing Executable element, according to the Name attribute of each Property element.
PropertyExpression	Additional constraints exist for the PropertyExpression element. For a description of the constraints, see PropertyExpressionElementType.	PropertyExpressionElementType	The PropertyExpression element serves the same purpose as specified for the Property element except that an expression that is evaluated at run time is contained in the element’s value that is stored in the Microsoft SQL Server Integration Services (SSIS) file format.
Executable	None	PrecedenceConstraintExecutableReferenceType	Contains a reference to an Executable upon which this PrecedenceConstraint instance acts.

The following table provides additional information about the attributes and types for the Property element that is declared inline in the complex type declaration. The Property element is an extension of the PropertyElementBaseType type with the addition of the Name attribute. This attribute is specified in the following table.

Attribute	Description
Name	Specifies the name of the Property element. Each named property has its own use and interpretation. The explanation for the interpretation of each named property is given with the definition of the type for the Name attribute.