Progress
Embedded SQL-92
Guide and Reference
NULL Values in an ORDER BY Clause
When you apply an ORDER BY clause to a column containing NULL values, the NULL value is treated as being greater than any non-NULL value. When the ordering is ascending, the NULL values sort at the end. When the ordering is descending, the NULL values sort first.
EXAMPLEThe following example shows the selection of employees (ename) ordered by the project numbers (projno). The ORDER BY clause specifies descending (DESC). The employees not assigned to a project are reported first, and those with the highest project numbers are reported last:
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