Input 

Document

• Min: 1

• Max: 1

• JSON

• Mapper

Each document should contain values referenced in the Aggregate fields and the GROUP-BY fields field set. If not, the input data is sent to the error view.

Output

Document

• Min: 1

• Max: 1

• JSON

• Mapper

Each document contains the mapped data that includes key-value entries of the GROUP-BY field name and its value, and a key-value entry of the Result field and its value, if processed successfully.

Error

Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter while running the Pipeline by choosing one of the following options from the When errors occur list under the Views tab. The available options are:

• Stop Pipeline Execution: Stops the current Pipeline execution when the Snap encounters an error.

• Discard Error Data and Continue: Ignores the error, discards that record, and continues with the rest of the records.

• Route Error Data to Error View: Routes the error data to an error view without stopping the Snap execution.

Learn more about Error handling in Pipelines.

Label*

Default Value: Aggregate
Example: Aggregate_Avg

String

Specify the name for the Snap. You can modify this to be more specific, especially if you have more than one of the same Snap in your Pipeline.

Aggregate fields*

Use this field set to define the type of Aggregate function to perform on the field and the key name to be used in the output. This field set contains the following fields:

• Function

• Field

• Result field

Function*

Default Value: SUM
Example: AVG

String

Select the functions that applies to the aggregate field value in the input data. The available functions and the supported datatypes are: 

• COUNT – all types.

• SUM – Number (Numeric string is converted to a number).

• MIN – Number, String, DateTime, LocalDateTime, LocalDate, LocalTime.

• MAX – Number, String, DateTime, LocalDateTime, LocalDate, LocalTime.

  • When using a date for MIN/MAX functions, change “$DATE.date" to "$DATE" in the Aggregate field.

• AVG – Number, DateTime, LocalDateTime, LocalDate, LocalTime (Numeric string is converted to a number).

• CONCAT – Concatenates all records separated by a pipe (|).

• UNIQUE_CONCAT – Concatenates all unique records separated by a pipe (|).

Field*

Default value: [None]
Example:  $Total or DateTime.parse($service)

String/Expression

Specify a JSON path to the field on which the Aggregate function should be applied such as $items.item. Learn more: JSONPath - XPath for JSON.

Result field*

Default value:  [None]
Example:  Revenue

String

Specify the field name to be used for mapped data in the output. This value is the aggregate computed result corresponding to the GROUP-BY field values.

GROUP-BY fields*

Use this field set to define field paths and names. If you leave this field blank, the Snap produces only one output document.

Field

Default value: [None]
Example:  $.Product.Name

String/Expression

Specify a JSON path for the GROUP-BY field.

Output field

Default value:  [None]
Example:  ProductName

String

Specify the GROUP-BY field name to be used in the output map data. If left blank, the Field path is used instead.

Checkbox

Select this checkbox if you want the Snap to produce integer results rounded half up.

Dropdown list

Select an option to specify if the input documents are sorted or not.

This option enables the Snap to verify if the input is sorted as it processes each document and performs the aggregation efficiently and displays an error if the records are not sorted.

The available options are:

• Unsorted: The input documents are not sorted.

• Ascending: The input documents are sorted in an ascending order.

• Descending: The input documents are sorted in descending order.

String/Expression

If the available memory is less than this property value while processing input documents, the Snap stops to fetch the next input document until more memory is available. This feature is disabled if this property value is 0.

String/Expression

If the Snap pauses longer than this property value while waiting for more memory available, it throws an exception to prevent the system from running out of memory.

Dropdown list

Select one of the three modes in which the Snap executes. Available options are:

• Validate & Execute: Performs limited execution of the Snap, and generates a data preview during Pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during Pipeline runtime.

• Execute only: Performs full execution of the Snap during Pipeline execution without generating preview data.

• Disabled: Disables the Snap and all Snaps that are downstream from it.

EXPRESSIONS_DETECTED

Expressions have been detected in Aggregate.

Remove all expressions.

ERR_UNSUPPORTED_AGGR_FUNCTION

The selected aggregate function is not supported.

Select a valid aggregate function.

INPUT_VARIABLES_NOT_SUBSTITUTED

One or more variables in the JSON file are not mapped.

Either remove non substituted variables starting with $ or map them using an upstream snap.

ERR_EDITOR_KEYWORDS_NOT_ESCAPED

Reserved characters are detected in the JSON key value pair.

Replace the reserved characters using # and [[ ]]. For example, replace ‘##’ as #[[##]]# to escape it.

ERR_MAPDB_VALUE_NULL

MapDB intermittently retrieves null for non-null value.

Use Sort Snap to sort the input data stream.

• The input documents for the Aggregate Snap contains two fields: value and group.

• The Snap is configured to perform the AVG, COUNT, MIN, and MAX functions on the presorted values in an ascending order.

• The GROUP-BY fields property contains $group field, which means the Snap groups input documents as per the $group value.

• The Sorted streams is set to Ascending because the input documents are presorted in an ascending order.
  Note: If the input documents are not in an ascending order, the Snap displays an exception.