BULK INSERT from one table to another all on the server
- by steve_d
I have to copy a bunch of data from one database table into another. I can't use SELECT ... INTO because one of the columns is an identity column. Also, I have some changes to make to the schema. I was able to use the export data wizard to create an SSIS package, which I then edited in Visual Studio 2005 to make the changes desired and whatnot. It's certainly faster than an INSERT INTO, but it seems silly to me to download the data to a different computer just to upload it back again. (Assuming that I am correct that that's what the SSIS package is doing). Is there an equivalent to BULK INSERT that runs directly on the server, allows keeping identity values, and pulls data from a table? (as far as I can tell, BULK INSERT can only pull data from a file)
Edit:
I do know about IDENTITY_INSERT, but because there is a fair amount of data involved, INSERT INTO ... SELECT is kinda of slow. SSIS/BULK INSERT dumps the data into the table without regards to indexes and logging and whatnot, so it's faster. (Of course creating the clustered index on the table once it's populated is not fast, but it's still faster than the INSERT INTO...SELECT that I tried in my first attempt)
Edit 2:
The schema changes include (but are not limited to) the following:
1. Splitting one table into two new tables. In the future each will have its own IDENTITY column, but for the migration I think it will be simplest to use the identity from the original table as the identity for the both new tables. Once the migration is over one of the tables will have a one-to-many relationship to the other.
2. Moving columns from one table to another.
3. Deleting some cross reference tables that only cross referenced 1-to-1. Instead the reference will be a foreign key in one of the two tables.
4. Some new columns will be created with default values.
5. Some tables aren’t changing at all, but I have to copy them over due to the "put it all in a new DB" request.
