Question for creating column comments in ddl script.

christophe_Gros

Question for creating column comments in ddl script. Hi, I'm working on a setup script with table creation. I would like to add comments on columns, but vertica doesn't allow it without a superprojection. On my understanding, this superprojection is only created at the first insert. So it seems i won't be able to create comments just after the create table statement.... Does anybody know if there's a workaround or if it can be implemented in next version. It would help for migration scripts from other db.... regards

Curtis_1

Hi Christophe, I'm not entirely sure I understand what you're trying to accomplish here. You can create a comment on a column with the "COMMENT ON COLUMN " command.

Certainly the first INSERT statement will create a superprojection for your table, but be aware that this is an unoptimized superprojection. You shouldn't rely on this to give you significant performance. If you want, you can create your own projection utilizing the CREATE PROJECTION syntax, and you could then load data into your table, and you won't be subject to the default projection that gets created from your load.

christophe_Gros

Hi Curtis and thanks for your reply, 
I'm just trying to run a ddl script with a create table and adding comment to the columns.
At this point, i do not have data and so no superprojection.
If I understand well, I have to put data in all my tables to create column comments, it's dispointing....