Missing or Null Values

For 0809, missing or null values, where possible, have been replaced in the standard files.

Part of the rationale behine this has been to simplify the process of using the files in SQL, and for reasons of consistency these changes have been applied to the files that are in SPSS format.

The changes applied are as follows:

• For numeric fields, null values have been replaced with -1.
• For text fields that are 2 or more characters long, the blank fields have been replaced with NA.
• For text fields that are 1 characters long, the blank fields have been replaced with N.
• Date files have not been affected and where no date has been entered, there will still be a null value.

Date last modified: 15th December 2008