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# Resource: Items

# Type: WixDataAggregatePipelineStages

# Action: project

# Link: https://dev.wix.com/docs/sdk/data-items-sdk/data/items/wix-data-aggregate-pipeline-stages/project.md

## Description: Adds a project stage to the aggregation pipeline.

The `project()` method adds a pipeline stage that transforms items by including, excluding, or reshaping fields. You can configure the projection by chaining one or more [`ProjectStage`](https://dev.wix.com/docs/sdk/backend-modules/data/items/project-stage/introduction.md) methods.

## Schema:

```json
 Method: project()
 Description: Adds a project stage to the aggregation pipeline.  The `project()` method adds a pipeline stage that transforms items by including, excluding, or reshaping fields. You can configure the projection by chaining one or more [`ProjectStage`](https://dev.wix.com/docs/sdk/backend-modules/data/items/project-stage/introduction.md) methods.
 Return type: REFERENCE<ProjectStage>
     Method: exclude(fieldNames)
     Description: Fields to exclude from the result.  When specified, excludes the specified field from the result. All other fields are included.
     Method parameters:
       param name:  fieldNames | type: Array<string> | description:  Fields to exclude from the result. Use dot notation to specify nested fields. For example, `user.name` or `product.price`.  Learn more about [field keys](https://support.wix.com/en/article/cms-formerly-content-manager-about-your-collection-fields#field-id-velo-by-wix-only). 
     Return type: REFERENCE<ProjectStage>
     Method: include(fieldNames)
     Description: Fields to include in the result.  When specified, the result includes only the specified fields. All other fields are excluded.
     Method parameters:
       param name:  fieldNames | type: Array<string> | description:  Fields to include in the result. Use dot notation to specify nested fields. For example, `user.name` or `product.price`.  Learn more about [field keys](https://support.wix.com/en/article/cms-formerly-content-manager-about-your-collection-fields#field-id-velo-by-wix-only). 
     Return type: REFERENCE<ProjectStage>
     Method: projectNested(stage, resultFieldName)
     Description: Creates nested fields by including, excluding, or reshaping fields.
     Method parameters:
       param name:  stage | type: ProjectStage | description:  Projected stage to nest. 
       param name:  resultFieldName | type: string | description:  Field to nest the projected stage in.  Learn more about [field keys](https://support.wix.com/en/article/cms-formerly-content-manager-about-your-collection-fields#field-id-velo-by-wix-only). 
     Return type: REFERENCE<ProjectStage>
     Method: reshape(expression, resultFieldName)
     Description: Reshapes a new field based on the specified expression. The result does not include the field used in the expression. For example, reshaping `basePrice` to add `tax` results in a new field `totalPrice` that does not include `basePrice` or `tax`.
     Method parameters:
       param name:  expression | type: Expression | description:  Expression to resolve. The result of the expression becomes the value of the new field. Learn more about using [expressions in aggregation pipelines](https://dev.wix.com/docs/sdk/backend-modules/data/items/wix-data-aggregate-pipeline-expressions/introduction.md). 
       param name:  resultFieldName | type: string | description:  Field to create in the result.  Learn more about [field keys](https://support.wix.com/en/article/cms-formerly-content-manager-about-your-collection-fields#field-id-velo-by-wix-only). 
     Return type: REFERENCE<ProjectStage>

```