The following restrictions apply to CLOB, BLOB, and UDT types in a NULLIF expression.
| Data Type | Restrictions |
|---|---|
| BLOB | A BLOB can only appear in the argument list when it is cast to BYTE or VARBYTE. |
| CLOB | A CLOB can only appear in the argument list when it is cast to CHAR or VARCHAR. |
| UDT | Multiple UDTs can appear in the argument list only when they are identical types and have an ordering definition. |