Comments on table columns

[Brett]

Howdy!

I am new to to the forums. Please be gentle. Can I add comments to table columns? I see in the docs we can add comments to projection columns but I want a high level comment, just on the table. Is that possible? I have to say, I'm not completely sure I understand what projections are. I'm coming from a MySQL database background.

Again, please be gentle, I'm a newbie

[nnani]

Hi Brett

Welcome to Vertica Forums !

For now, Vertica allows you to add comments on column level in projection and not tables.
So it is possible that two different projection referring a table will have different comments on same column.

If you follow a standard for comments on column on every projection for a table .i.e.
Let say you have table A with 5 3 columns
Table A has two projections A1 and A2 each with 3 columns, then you have to make sure the comments added to each column in both projection are exactly same.

This way you can achieve high level comment.

I'm not completely sure I understand what projections

In short, Projections are nothing but materialized views

For more information on achieving a high level look on comments you can refer the below post.
I am sure after going through it, your doubts will be cleared
http://www.vertica-forums.com/viewtopic ... ents#p1702

Hope this helps..

[Brett]

nnani, thank you for getting back to me. So for self-documenting purposes myself I need to comment every projection column. I suppose that makes sense, but it's hard to automate. It was easier in Oracle. Maybe Vertica needs to look into inheriting comments from the tables?