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• If the dataset contains no schema, the Split Column transformation used. This transformation attempts to find a single consistent pattern or a sequence of patterns in row data to demarcate the end of individual values (fields). 

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  NOTE:  Avoid creating datasets that are wider than 2500 1000 columns. Performance can degrade significantly on very wide datasetseven a much more narrow dataset. You should limit yourself to under 500 columns in your dataset.

  
  

• If the dataset contains a schema, that information is used to demarcate the columns in the dataset. 

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