IBM PureData System for Analytics, Version 7.1

String and non-string fields

If an input field corresponds to a column declared as char, nchar, varchar, or nvarchar, the system considers it a string field. All other types are considered non-string fields. This distinction is important because spaces are significant within string fields but not in non-string fields.

Note: An empty field or a field that contains only spaces can represent a legitimate string value, but can never be a legitimate non-string value.

The system uses the following rules based on whether the field is a string field:

For a string field, all characters from the beginning of the field to the terminating delimiter or end of row sequence contribute to the value of the field.
For a non-string field, the system skips any leading spaces, interprets or converts the contents of the field, and skips any trailing spaces.

The string and non-string distinction also affects the details of how a field indicates that it is null. For more information, see Handle the absence of a value.