The default value for this option is ?. This means a question mark character is used to represent a null value resulting from a SELECT statement. This string is also used in an import file to indicate that the corresponding column should be assigned a null value.
Many spreadsheet and database applications can save data in tab-delimited format. In most cases, they do not allow you to specify a null character, but simply write nothing to the file. If you want to import data from a file like this, set this field to a zero length string by deleting the contents of the field.
- Select .
- Click the Data Format tab.
In Display this string for Null data fields, fill in the string desired.
Use the string you have defined for the display of NULL values. The default is a question mark (?). This string, possibly quoted, should be the only thing between the surrounding delimiter characters.