This table lists unsupported syntax or features. Attempt to use them causes an error.
| Unsupported Syntax | Explanation |
|---|---|
| INSERT ... SELECT | None. |
| Positioned UPDATE | A WHERE clause cannot use an updatable cursor to do a positioned UPDATE. |
| UPDATE FROM | None. |
| UPDATE WHERE subquery | A WHERE clause cannot use a subquery either to specify the primary index or to constrain a non-index column. |
| UPDATE SET primary_index_column | You cannot update a primary index column because any change to the rowhash value for a row affects its distribution. |
| UPDATE SET partitioning_column | You cannot update a partitioning column because any change to the partitioning for a row affects its location. |
| UPDATE SET identity_column | You cannot update GENERATED ALWAYS identity column values. |
| UPDATE SET PARTITION | You cannot update system-derived PARTITION values. If PARTITION is a user-named column in a table, and not a GENERATED ALWAYS identity column, then it can be updated. |