# Field
<a name="API_Field"></a>

A key-value pair that describes a property of a pipeline object. The value is specified as either a string value (`StringValue`) or a reference to another object (`RefValue`) but not as both.

## Contents
<a name="API_Field_Contents"></a>

 ** key **   <a name="DP-Type-Field-key"></a>
The field identifier.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 256.  
Pattern: `[\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*`   
Required: Yes

 ** refValue **   <a name="DP-Type-Field-refValue"></a>
The field value, expressed as the identifier of another object.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 256.  
Pattern: `[\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*`   
Required: No

 ** stringValue **   <a name="DP-Type-Field-stringValue"></a>
The field value, expressed as a String.  
Type: String  
Length Constraints: Minimum length of 0. Maximum length of 10240.  
Pattern: `[\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*`   
Required: No

## See Also
<a name="API_Field_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/datapipeline-2012-10-29/Field) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/datapipeline-2012-10-29/Field) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/datapipeline-2012-10-29/Field)