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USING Keyword

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Summary

The USING directive is similar to the C# using Directive in that it allows to shorten function, type, extention methods, and UDO path names.

Syntax

Using_Directive :=                                                                                       
     'USING' 
     (csharp_namespace | Alias '=' csharp_namespace_or_type ['.' class]).

The scope of a using directive is limited to the file in which it appears.

Create a using alias to make it easier to qualify an identifier to a namespace or type. The right side of a using alias directive must always be a fully-qualified type regardless of the using directives that come before it.

Create a using directive to use the types in a namespace without having to specify the namespace. A using directive does not give you access to any namespaces that are nested in the namespace you specify.

Examples

Specify namespace
In this example we default C# namespace resolution to the specified namespace:

DECLARE @ input string = "somejsonfile.json";

REFERENCE ASSEMBLY [Newtonsoft.Json];
REFERENCE ASSEMBLY [Microsoft.Analytics.Samples.Formats];

USING Microsoft.Analytics.Samples.Formats.Json;

@data0 = 
    EXTRACT IPAddresses string
    FROM @input
    USING new JsonExtractor("Devices[*]");

...

Alias namespace
In this example we use an alias to shorten the namespace path with an alias:

DECLARE @ input string = "somejsonfile.json";

REFERENCE ASSEMBLY [Newtonsoft.Json];
REFERENCE ASSEMBLY [Microsoft.Analytics.Samples.Formats];

USING json = Microsoft.Analytics.Samples.Formats.Json;

@data0 = 
    EXTRACT IPAddresses string
    FROM @input
    USING new json.JsonExtractor("Devices[*]");

...

Alias Type
In the following example, we alias the full type name. Note that we support quoting the name to allow all uppercase namespaces.

DECLARE @ input string = "somejsonfile.json";

REFERENCE ASSEMBLY [Newtonsoft.Json];
REFERENCE ASSEMBLY [Microsoft.Analytics.Samples.Formats];

USING json = [Microsoft.Analytics.Samples.Formats.Json.JsonExtractor];

@data0 = 
    EXTRACT IPAddresses string
    FROM @input
    USING new json("Devices[*]");

...

Additional Examples
See the examples under:

See Also