Skagi, a kakoi smysl v tom, chtoby ydalat' s "order by t.x"??

From Oracle's Doc::
Restrictions on the dml_table_expression_clause:

You cannot execute this statement if table (or the base table of view) contains any domain indexes marked IN_PROGRESS or FAILED.
You cannot insert into a partition if any affected index partitions are marked UNUSABLE.
You cannot specify the ORDER BY clause in the subquery of the dml_table_expression_clause.
You cannot delete from a view except through INSTEAD OF triggers if the view's defining query contains one of the following constructs:
A set operator
A DISTINCT operator
An aggregate or analytic function
A GROUP BY, ORDER BY, CONNECT BY, or START WITH clause
A collection expression in a SELECT list
A subquery in a SELECT list
Joins (with some exceptions). See Oracle9i Database Administrator's Guide for details.
If you specify an index, index partition, or index subpartition that has been marked UNUSABLE, the DELETE statement will fail unless the SKIP_UNUSABLE_INDEXES parameter has been set to true.

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