Batch Merger*¶

This stage generates a group tag for each record in the current batch based on the specified condition. The records are then merged with the same tag and output in a single record. The function of this stage includes:

Supporting 2 methods for generating group keys: by record field value or EL expression.
Incompatible with old data formats, i.e. cannot filter data by ModelId::PointId.

Configuration¶

The configuration tabs for this stage are General, Basic, Input/Output, and Group Key.

General¶

Name	Required?	Description
Name	Yes	The name of the stage.
Description	No	The description of the stage.
Stage Library	Yes	The streaming operator library to which the stage belongs.
Required Fields	No	The fields that the data records must contain. If the specified fields are not included, the record will be filtered out.
Preconditions	No	The conditions that must be satisfied by the data records. Records that do not meet the conditions will be filtered out. For example, `${record:value('/value') > 0}`. For the syntax of EL expressions, see Expression Language.
On Record Error	Yes	The processing method for error data. Discard: Error data will be discarded and ignored Send to Error: Error messages will be reported Stop Pipeline: The pipeline will be stopped

Basic¶

Name	Required?	Description
Quality Filter	No	Filter the data according to the data quality. Only records that meet the quality conditions will be processed by this stage.

Input/Output¶

Name	Required?	Description
Input Measurement	Yes	Data input point
Output Measurement	Yes	Data output point

Group Key¶

Name	Required?	Description
Key Generate Method	Yes	Select the method for generating group tags. The options are By Record Field Value and By EL Expression.
Fields	No	When By Record Field Value is selected, select or specify the field name.
EL Expression	No	When By EL Expression is selected, type the expression for generating the group keys.

Output Results¶

The output results of this stage are included in the attr struct. The description of the fields are as follows:

Name	Data Type	Description
crossBatch	Map	The collection of records with the same group key.

Note

The values of modelIdPath, pointId, and modelId in the output of this operator are the default strings: modelIdPath, pointId, and modelId respectively.

Output Example¶

../../../_images/cross_batch_merger11.png