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Script Task

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Applies to: SQL Server SSIS Integration Runtime in Azure Data Factory

The Script task provides code to perform functions that are not available in the built-in tasks and transformations that SQL Server Integration Services provides. The Script task can also combine functions in one script instead of using multiple tasks and transformations. You use the Script task for work that must be done once in a package (or once per enumerated object), instead than once per data row.

You can use the Script task for the following purposes:

  • Access data by using other technologies that are not supported by built-in connection types. For example, a script can use Active Directory Service Interfaces (ADSI) to access and extract user names from Active Directory.

  • Create a package-specific performance counter. For example, a script can create a performance counter that is updated while a complex or poorly performing task runs.

  • Identify whether specified files are empty or how many rows they contain, and then based on that information affect the control flow in a package. For example, if a file contains zero rows, the value of a variable set to 0, and a precedence constraint that evaluates the value prevents a File System task from copying the file.

If you have to use the script to do the same work for each row of data in a set, you should use the Script component instead of the Script task. For example, if you want to assess the reasonableness of a postage amount and skip data rows that have very high or low amounts, you would use a Script component. For more information, see Script Component.

If more than one package uses a script, consider writing a custom task instead of using the Script task. For more information, see Developing a Custom Task.

After you decide that the Script task is the appropriate choice for your package, you have to both develop the script that the task uses and configure the task itself.

Writing and Running the Script that the Task Uses

The Script task uses Microsoft Visual Studio Tools for Applications (VSTA) as the environment in which you write the scripts and the engine that runs those scripts.

VSTA provides all the standard features of the Visual Studio environment, such as the color-coded Visual Studio editor, IntelliSense, and Object Explorer. VSTA also uses the same debugger that other Microsoft development tools use. Breakpoints in the script work seamlessly with breakpoints on Integration Services tasks and containers. VSTA supports both the Microsoft Visual Basic and Microsoft Visual C# programming languages.

To run a script, you must have VSTA installed on the computer where the package runs. When the package runs, the task loads the script engine and runs the script. You can access external .NET assemblies in scripts by adding references to the assemblies in the project. Currently we dont support .NET Core and .NET standard assembly references.

Note

Unlike earlier versions where you could indicate whether the scripts were precompiled, all scripts are precompiled in SQL Server 2008 Integration Services (SSIS) and later versions. When a script is precompiled, the language engine is not loaded at run time and the package runs more quickly. However, precompiled binary files consume significant disk space.

Configuring the Script Task

You can configure the Script task in the following ways:

  • Provide the custom script that the task runs.

  • Specify the method in the VSTA project that the Integration Services runtime calls as the entry point into the Script task code.

  • Specify the script language.

  • Optionally, provide lists of read-only and read/write variables for use in the script.

You can set these properties through SSIS Designer or programmatically.

Configuring the Script Task in the Designer

The following table describes the ScriptTaskLogEntry event that can be logged for Script task. The ScriptTaskLogEntry event is selected for logging on the Details tab of the Configure SSIS Logs dialog box. For more information, see Integration Services (SSIS) Logging.

Log entry Description
ScriptTaskLogEntry Reports the results of implementing logging in the script. The task writes a log entry for each call to the Log method of the Dts object. The task writes these entries when the code is run. For more information, see Logging in the Script Task.

For more information about the properties that you can set in SSIS Designer, see the following topics:

For more information about how to set these properties in SSIS Designer, see the following topic:

Configuring the Script Task Programmatically

For more information about programmatically setting these properties, see the following topic:

Script Task Editor (General Page)

Use the General page of the Script Task Editor dialog box to name and describe the Script task.

To learn more about the Script task, see Script Task and Configuring the Script Task in the Script Task Editor. To learn about programming the Script task, see Extending the Package with the Script Task.

Options

Name
Provide a unique name for the Script task. This name is used as the label in the task icon.

Note

Task names must be unique within a package.

Description
Type a description of the Script task.

Script Task Editor (Script Page)

Use the Script page of the Script Task Editor dialog box to set script properties and specify variables that can be accessed by the script.

Note

In SQL Server 2008 Integration Services (SSIS) and later versions, all scripts are precompiled. In earlier versions, you set a PrecompileScriptIntoBinaryCode property to specify that the script was precompiled.

To learn more about the Script task, see Script Task and Configuring the Script Task in the Script Task Editor. To learn about programming the Script task, see Extending the Package with the Script Task.

Options

ScriptLanguage
Select the scripting language for the task, either Microsoft Visual Basic or Microsoft Visual C#.

After you have created a script for the task, you cannot change the value of the ScriptLanguage property.

To set the default scripting language for the Script task, use the Scripting language option on General page of the Options dialog box. For more information, see General Page.

EntryPoint
Specify the method that the Integration Services runtime calls as the entry point into the code of the Script task. The specified method must be in the ScriptMain class of the Microsoft Visual Studio Tools for Applications (VSTA) project The ScriptMain class is the default class generated by the script templates.

If you change the name of the method in the VSTA project, you must change the value of the EntryPoint property.

ReadOnlyVariables
Type a comma-separated list of read-only variables that are available to the script, or click the ellipsis (...) button and select the variables in the Select variables dialog box.

Note

Variable names are case sensitive.

ReadWriteVariables
Type a comma-separated list of read/write variables that are available to the script, or click the ellipsis (...) button and select the variables in the Select variables dialog box.

Note

Variable names are case sensitive.

Edit Script
Opens the VSTA IDE where you can create or modify the script.

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