Source SPSS dataset, in source variable order:
| case | age | sex | satisfaction |
|---|---|---|---|
| 1 | 32 | 1 | 8 |
| 2 | 47 | 2 | system-missing |
The corresponding dedicated SQL table has the same rectangular shape plus the technical ordering column:
__case_ordinal |
age |
sex |
satisfaction |
|---|---|---|---|
| 1 | 32 | 1 | 8 |
| 2 | 47 | 2 | NULL |
NULL represents SPSS numeric system-missing only. A user-missing code such as 9 remains stored as 9 and is described by an missing_rule record. Likewise, sex labels such as 1 = "Male" and 2 = "Female" are held in value-label metadata; the SQL table continues to store 1 and 2.
On export, rows are read by __case_ordinal, variables are emitted in metadata source order, and the technical ordinal column is omitted.