Merge
We assume that you have already learned what is described in:
If you want to find the right Transformer for your purposes, see Transformers Comparison.
Short Summary
Merge merges and sorts data records from two or more inputs.
| Component | Same input metadata | Sorted inputs | Inputs | Outputs | Java | CTL |
|---|---|---|---|---|---|---|
| Merge | yes | yes | 2-n | 1 | - | - |
Abstract
Merge receives sorted data records through two or more input ports. (Metadata of all input ports must be the same.) It gathers all input records and sorts them in the same way on the output.
![[Important]](figures/important.png) | Important |
|---|---|
Remember that all key fields must be sorted in ascending order! |
Icon
Ports
| Port type | Number | Required | Description | Metadata |
|---|---|---|---|---|
| Input | 0-1 | yes | For input data records | Any |
| 2-n | no | For input data records | Input 01) | |
| Output | 0 | yes | For merged data records | Input 01) |
Legend:
1): Metadata can be propagated through this component. All output metadata must be the same.
Merge Attributes
| Attribute | Req | Description | Possible values |
|---|---|---|---|
| Basic | |||
| Merge key | yes | Key according to which the sorted records are merged. (Remember that all key fields must be sorted in ascending order!) See Group Key for more information.1) | |
| Equal NULL | By default, records with null values of key fields are
considered to be different. If set to true,
they are considered to be equal. | false (default) | true | |
Legend:
1): Metadata can be propagated through this component. All output metadata must be the same.