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# Resource: Items

# Type: WixDataAggregatePipelineExpressions

# Action: toUpper

# Link: https://dev.wix.com/docs/sdk/data-items-sdk/data/items/wix-data-aggregate-pipeline-expressions/to-upper.md

## Description: Converts an expression to uppercase.

The `toUpper()` method configures the aggregation pipeline to convert the specified expression to uppercase.

## Schema:

```json
 Method: toUpper(expression)
 Description: Converts an expression to uppercase.  The `toUpper()` method configures the aggregation pipeline to convert the specified expression to uppercase.
 Method parameters:
   param name:  expression | type: Expression | description:  Expression to convert to uppercase. Expression must resolve to a string. 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). 
 Return type: REFERENCE<ToUpperExpression>

```