How to reject external table rows with some blank columns

Question

How to reject external table rows with some blank columns
I have an external table and I would like to reject rows when a number of fields are empty. Here are the details.
CREATE TABLE EXTTAB (
ID NUMBER(10),
TSTAMP DATE,
C1 NUMBER(5,0),
C2 DATE,
C3 FLOAT(126)
ORGANIZATION EXTERNAL (
TYPE ORACLE_LOADER
DEFAULT DIRECTORY EXT_DAT_DIR
ACCESS PARAMETERS (
RECORDS DELIMITED BY NEWLINE
LOAD WHEN (NOT (c1 = BLANKS AND c2 = BLANKS AND c3 = BLANKS))
LOGFILE EXT_LOG_DIR:'exttab.log'
BADFILE EXT_BAD_DIR:'exttab.bad'
DISCARDFILE EXT_BAD_DIR:'exttab.dsc'
FIELDS TERMINATED BY "|"
LRTRIM
MISSING FIELD VALUES ARE NULL
REJECT ROWS WITH ALL NULL
FIELDS (
ID,
TSTAMP DATE 'YYYYMMDDHH24MISS',
C1,
C2 DATE 'YYYYMMDDHH24MISS',
C3
) LOCATION ('dummy.dat')
REJECT LIMIT UNLIMITED
So, as you can see from the LOAD WHEN clause, I'd like to reject rows when C1, C2 and C3 are empty.
The above statement works fine and creates the table. However when I am trying to load data using it, the following error is produced:
ORA-29913: error in executing ODCIEXTTABLEOPEN callout
ORA-29400: data cartridge error
KUP-00554: error encountered while parsing access parameters
KUP-01005: syntax error: found "not": expecting one of: "double-quoted-string, identifier, (, number, single-quoted-string"
KUP-01007: at line 1 column 41
ORA-06512: at "SYS.ORACLE_LOADER", line 14
ORA-06512: at line 1
It seems that external tables driver does not understand the "NOT (...)" condition. Could anyone suggest how I can achieve what I want in a different way?
Thank you.
Denis

Answer 1

Another method would be to simply remove the "LOAD WHEN condition" and create a view on the external table which filters the data.
CREATE EXTTAB_VIEW AS
SELECT * FROM EXTTAB
WHERE not (c1 is null and c2 is null and c3 is null);