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• A missing value is any value that either contains no content or is non-existent. 
  • An example of a non-existent value is a cell in a column of integers that has no value in it. In this special case, the missing value is called a null value. 
  • Null values are converted to missing values during import. For more information, see Manage Null Values. 

• Values that are spaces (one or more presses of the SPACEBAR) or tabs (one or more presses of the TAB key) are not missing values.

  Tip

  Tip: To trim whitespace out of a column, use the following transformation: D trans Type step p01Name Columns p01Value column1 p02Name Formula p02Value TRIM(column1) SearchTerm Edit column with formula This step may increase the number of missing values (for values that contain only whitespace characters) and the number of instances of matching values (for values that have spaces before and after an alphanumeric value).

• Return (\n) and newline (\l)  are considered missing.

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For more information on inserting timezone metadata, see Add Lookup Data.