Wherescape / ETL / SQL DB Fact表-添加列

Question

We have a star schema designed in Wherescape. The task is to add new columns to the Fact table. The fact table have around 30gb in it. Is it possible to add columns without deleting the fact table? Or what technique should be used to retain the current data in the fact table, and at the same time have the new columns available. I keep getting a timeout error if I just try to add columns in management studio.

I think the guy before me actually just modified it in Wherescape (not too sure). In anycase if I have to do it manually in management studio, that works for me too.

thanks Gemmo

Answer 1

Can't really do this without deleting the table. It's too big and no matter what you do, it will time out. Back up the table, delete it and create the table with the new structure. You'll just have to put the data in again. No shortcuts. For smaller tables, you can easily add a column no problem.

Answer 2

Best way to do this is to add the column to the metadata and then right click on your table/object and then click "Validate against the database".

• this would allow you to alter the table instead of having to take the long route of moving data into a temp table, recreating the table and moving the data back.