Set the Properties of a User-Defined Variable
To set the properties of a user-defined variable in Integration Services, you can use one of the following features:
Variables window.
Properties window. The Properties window lists properties for configuring variables that are not available in the Variables window: Description, EvaluateAsExpression, Expression, ReadOnly, ValueType, and IncludeInDebugDump.
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Integration Services also provides a set of system variables whose properties cannot be updated, with the exception of the RaiseChangedEvent property.
Setting Expressions on Variables
When you use the Properties window to set expressions on a user-defined variable:
The value of a variable can be set by the Value or the Expression property. By default, the EvaluateAsExpression property is set to False and the value of the variable is set by the Value property. To use an expression to set the value, you must first set EvaluateAsExpression to True, and then provide an expression in the Expression property. The Value property is automatically set to the evaluation result of the expression.
The ValueType property contains the data type of the value in the Value property. When Value is set by an expression, ValueType is automatically updated to a data type that is compatible with the evaluation result of the expression. For example, if Value contains 0 and ValueType property contains Int32 and you then set Expression to GETDATE(), Value contains the current date and time and ValueType is set to DateTime.
The Properties window for the variable provides access to the Expression Builder dialog box. You can use this tool to build, validate, and evaluate expressions. For more information, see Expression Builder and Integration Services (SSIS) Expressions.
When you use the Variables window to set expressions on a user-defined variable:
To use an expression to set the variable value, first confirm that the variable data type is compatible with the evaluation result of the expression and then provide an expression in the Expression column of the Variables window. The EvaluateAsExpression property in the Properties window is automatically set to True.
When you assign an expression to a variable, a special icon marker displays next to the variable. This special icon marker also displays next to connection managers and tasks that have expressions set on them.
The Variables window for the variable provides access to the Expression Builder dialog box. You can use this tool to build, validate, and evaluate expressions. For more information, see Expression Builder and Integration Services (SSIS) Expressions.
In both the Variables and Properties window, if you assign an expression to the variable, and EvaluateAsExpression is set to True, you cannot change the variable data type.
Setting the Namespace and Name Properties
The values of the Name and Namespace properties must begin with an alphabetic character letter as defined by the Unicode Standard 2.0, or an underscore (_). Subsequent characters can be letters or numbers as defined in the Unicode Standard 2.0, or the underscore (_).
Using the Variables Window to Set Properties
To set the properties of a variable by using the Variables window
In SQL Server Data Tools (SSDT), open the Integration Services project that contains the package you want.
In Solution Explorer, right-click the package to open it.
On the SSIS menu, click Variables.
You can optionally display the Variables window by mapping the View.Variables command to a key combination of your choosing on the Keyboard page of the Options dialog box.
Optionally, in the Variables window click Grid Options, and then select the columns to appear in the Variables window and select the filters to apply to the list of variables.
Select the variable in the list, and then update values in the Name, Data Type, Value, Namespace, Raise Change Event, Description, and Expression columns.
Select the variable in the list, and then click Move Variable to change the scope.
To save the updated package, on the File menu, click Save Selected Items.
Using the Properties Window to Set Properties
To set the properties of a variable by using the Properties window
In SQL Server Data Tools (SSDT), open the Integration Services project that contains the package you want.
In Solution Explorer, right-click the package to open it.
On the View menu, click Properties Window.
In SSIS Designer, click the Package Explorer tab and expand the Package node.
To modify variables with package scope, expand the Variables node; otherwise, expand the Event Handlers or Executables nodes until you locate the Variables node that contains the variable that you want to modify.
Click the variable whose properties you want to modify.
In the Properties window, update the read/write variable properties. Some properties are read/read only for user-defined variables.
For more information about the properties, see Integration Services (SSIS) Variables.
To save the updated package, on the File menu, click Save Selected Items.
Zobacz także
Zadania
Add, Delete, Change Scope of User-Defined Variable in a Package