Merge - ora-00904 - Invalid Identifier.

Hi Folks, I'm pretty new no Oracle and SQL and have been trying to learn as I go. Can someone please help?
I have to "UPSERT" tables on a monthly basis from text files from a data supplier.

I plan to replace each text file into staging table, Create a trigger on the staging table to "MERGE" the data onto a final table. I have had to do it this way as sqlldr will not alllow merge.

I've been trying to get the merge working on it's own before inclusion in a trigger but am getting ORA-00904 - Invalid Identifier. I have checked and re-checked and cannot spot the error. Any clues anyone?

MERGE INTO "LOAD_TEST_T"
USING (SELECT * from "LOAD_TEST_IN")
ON ("LOAD_TEST_T"."PZ"="LOAD_TEST_IN"."PZ") WHEN MATCHED THEN
UPDATE
        SET "LOAD_TEST_T"."TEXT"="LOAD_TEST_IN"."TEXT" WHEN NOT MATCHED THEN
INSERT
("LOAD_TEST_T"."PZ", "LOAD_TEST_T"."TEXT")
VALUES
("LOAD_TEST_IN"."PZ", "LOAD_TEST_IN"."TEXT");
I'll be extremely embarrassed if it's a typo......... Received on Wed Apr 25 2007 - 09:28:32 CDT