Why the comment is considered ddl statement

Hi all

In an interview, asked me 'why comment is considered a DDL statement if it does change not the structure of an object'.

My answer was if it does not directly change of structure of an object (table, column, view etc.) and however it provides information on this subject.

Comment also adds data in the table data dictionary.

But the interviewer was not satisfied with my answer.

I tried to look for the answer on the web, but did not find a lot of details.

Could someone please suggest something on that.

SomeoneElse says:

Because it performs a validation.

Each Oracle DDL commits implicitly but DDL is not all that implicitly commits. And this not is not commit defines what talking about DDL statement. One of the features of the DOF is active DDL change attributes of objects and that is exactly what COMMENT. He adds comments of the table/column and we can discuss how significant are comments, but it does not change the comments in fact are attributes of objects.

SY.

Tags: Database

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