IBM BPM, V8.0.1, All platforms > Authoring services in Integration Designer > Defining and transforming data > Transforming data > Transforming data using XML maps > Functions and transforms > IBM supplied transform types
XML Transform: Join
Join multiple input arrays into a single output based on a common value, similar to the way tables are joined in database operations. The join transform replaces the merge transform that was available in previous releases.
Purpose
Joins elements from two or more inputs into a single output. At least one of the input elements must be an array. Input arrays need not be the same size during execution. The output element can be an array or single element but must be a complex type.
- Join expression
- When there are two or more input arrays, the criteria on which to join these arrays can be specified in the join expression which is located in the General properties page. The join expression is a boolean expression analogous to the where clause in a database operation.
If no join expression is specified, the size of the target array will be the Cartesian product of the sizes of the input arrays.
- Cardinality
- The Cardinality properties page allows you to filter any of the input arrays before they are joined.
- Order
- The Order properties page allows you to indicate which order the input arrays will be processed which in turn will determine the order of the target array.
The Join transform contains nested maps that you need to complete. Click the transform or right-click and select Edit to open the contained nested map. Map the elements in the nested map and apply the appropriate transforms.
The Join transform replaces the Merge transform from previous releases. Merge transforms will be converted to Join transforms when the map is opened in the map editor. If the merge does not contain any repeatable inputs then it will be converted to a local transform.