Difference between Merge Transformation and Union all transformations.

 Merge Transformation: This does the task of merging data from 2 sources to single output. This is useful when we need to break the data flow path to a separate error path and once the error is handled, merge that back to the main data flow. To apply this transformation, the data should be sorted first and the metadata information for the 2 paths should be the same. The sorting can be done by applying sort transformation before the merge or by providing an ORDER BY clause in the source connection.

Union All Transformation: Union all transformation working is similar to merge transformation but the only difference is that this does not require sorted data. Data from different sources are transformed and combined into a single output.

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