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sqloracle-databasealter-table

Incorrect railroad diagram for ALTER TABLE with multiple out-of-line constraints?

Currently using 18c but this apparent inconsistency is present in earlier versions (certainly back to 11g).

In this particular case, I am adding multiple out-of-line constraints to an existing table.

All railroad diagrams are found here: https://docs.oracle.com/en/database/oracle/oracle-database/18/sqlrf/ALTER-TABLE.html

This is the railroad diagram for ALTER TABLE:

enter image description here

Then, this is the railroad diagram for constraint_clauses:

enter image description here

Finally, this is the railroad diagram for out_of_line_constraint:

enter image description here

There are no ( and ) or a , in the railroad diagram. But the SQL query must have them.

Here is the code that works:

Create table a ( x number );

Alter table a add (
  constraint x1 check ( x > 0 ),
  constraint x2 check ( x < 10)
);

Where is my mistake in reading and interpreting the railroad diagram? Is there something else I must know?

Solution

  • You don't need parentheses or commas. This works:

    alter table a 
  add constraint x1 check (x > 0)
  add constraint x2 check (x < 10);

    But it's a documentation bug either way, as the railroad diagram does not indicate that the "constraint_clauses" reference is repeatable.