Merge Node

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This node allows you to merge two input data streams into one output data stream. The merge is performed on a row-per-row basis or by key merge performing a left-outer-join. The method is determined on what input columns are fed into the merge node.

NOTE 1: If there are no Merge Key columns then a row-per-row merge is performed. If Input 1 has 100 rows and Input 2 has 110 rows, then the output will consist of 110 rows where the data for columns in Input 1 will be padded with missing data '?' for the last 10 rows. The same goes if Input 2 has less rows than Input 1.

NOTE 2: If there are columns from Input 1 and 2 with a common name but different type then the Analyse will fail. You will have to change the name or type of the column in Input 2 to match the one in Input 1 or vise versa.

NOTE 3: The Merge by Keys can be a memory exhausting process, so choose your Merge Key columns wisely. The reason been that every row in Input 1 is matched to every row in Input 2, that has matching key values, and a new row is created for the output. That is, you can have 100 rows for Input 1 and 10 rows for Input 2 which could produce 100x10=1000 rows of output if every row from Input 1 matched every row in Input 2.