SAND CDBMS SQL Reference Guide
SAND CDBMS SQL Database Objects and Language Elements

Other SAND CDBMS SQL Language Elements

Nulls

A null is a representation of a missing or unknown value. Nulls are not equivalent to zero, blank spaces, or the empty string. In fact, no two nulls are equivalent.

Null Assignments

The following SQL UPDATE statement illustrates the assignment of null values to an entire column:

UPDATE president SET byear = NULL;

A WHERE clause may be added in order to assign null values to a column only for selected rows. SAND CDBMS assigns nulls automatically to columns that are omitted from an INSERT statement on a particular table.

Refer to Other Topics: Nulls for more information about the behavior of nulls in SQL clauses.