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answers:

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I have a large (multi-GB) data file exported from an Oracle table. I want to import this data into another Oracle instance, but I want the table name to be different from the original table. Is this possible? How?

Both importing and exporting systems are Oracle 11g. The table includes a BLOB column, if this makes any difference.

Thanks!

UPDATES:

The idea here was to update a table while keeping the downtime on the system that's using it to a minimum. The solution (based on Vincent Malgrat's answer and APC's update) is:

  1. Assuming our table name is A
  2. Make a temp schema TEMP_SCHEMA
  3. Import our data into TEMP_SCHEMA.A
  4. CREATE REAL_SCHEMA.B AS SELECT * FROM TEMP_SCHEMA.A
  5. DROP TABLE REAL_SCHEMA.A Rename REAL_SCHEMA.A to REAL_SCHEMA.A_OLD
  6. Rename REAL_SCHEMA.B to REAL_SCHEMA.A
  7. DROP REAL_SCHEMA.A_OLD

This way, the downtime is only during steps 4 and 5, both should be independent of data size. I'll post an update here if this does not work :-)

A: 

Just import it into a table with the same name, then rename the table.

Gandalf
+1 Agreed. If the table already exist, you must rename it, then import the data, rename the new table to the name you want and then rename the original table back to its original name.
Aaron Digulla
I have a system that's using the table in question (call it "A") and I don't want to take it down for the time it will take me to do the import. I was hoping to do this: import data into table "B", then drop "A" and rename "B" to "A". That would avoid hours of downtime for the import.
scrible
+1  A: 

Hi scrible,

I suppose you want to import the table in a schema in which the name is already being used. I don't think you can change the table name during the import. However, you can change the schema with the FROMUSER and TOUSER option. This will let you import the table in another (temporary) schema.

When it is done copy the table to the target schema with a CREATE TABLE AS SELECT. The time it will take to copy the table will be negligible compared to the import so this won't waste too much time. You will need two times the disk space though during the operation.

Update

As suggested by Gary a cleverer method would be to create a view or synonym in the temporary schema that references the new table in the target schema. You won't need to copy the data after the import as it will go through directly to the target table.

Vincent Malgrat
I believe this will work! Thank you. One small wrinkle here is that the table is mostly BLOBs by volume, so the CREATE TABLE AS SELECT will take a while, but I can deal with that.
scrible
IF you precreate the object in the TOUSER as a view with SELECT * FROM destuser.newtable, the inserts will go through the view direct to the new table. At least that would work with IMP IGNORE=Y. Worth trying with a synonym too.
Gary
@Gary: good suggestion I updated my answer
Vincent Malgrat
+2  A: 

If you are using the old EXP and IMP utilities you cannot do this. The only option is to import into a table of the same name (although you could change the schema which owns the table.

However, you say you are on 11g. Why not use the DataPump utility introduced in 10g, which replaces Import and Export. Because in 11g that utility offers the REMAP_TABLE option which does exactly what you want.

edit

Having read the comments the OP added to another response while I was writing this, I don't think the REMAP_TABLE option will work in their case. It only renames new objects. If a table with the original name exists in the target schema the import fails with ORA-39151. Sorry.

edit bis

Given the solution the OP finally chose (drop existing table, replace with new table) there is a solution with Data Pump, which is to use the TABLE_EXISTS_ACTION={TRUNCATE | REPLACE} clause. Choosing REPLACE drops the table whereas TRUNCATE merely, er, truncates it. In either case we have to worry about referential integrity constraints, but that is also an issue with the chosen solution.

I post this addendum not for the OP but for the benefit of other seekers who find this page some time in the future.

APC
Thank you, I will keep that in mind for the next time. At this point I have to use the originally exported data file (produced by exp).
scrible
+1: nice, I was looking for it in the doc, I was pretty sure it is possible with expdp
Vincent Malgrat
A: 

Create a view as select * from ... the table you want to import into, with the view matching the name of the table in the export. Ignore errors on import.

David Aldridge
AFAIK, the view cannot have the same name as the existing table.
IronGoofy
No, you create the view with the name that the import file uses, and the table with the name you want the table to have.
David Aldridge