sqlloader with constraint NOT NULL in oracle table - oracle

Question

I'm entering values from a CSV file to an Oracle table using a SQL*Loader script. In this table there are fields with NOT NULL constraints. In my CSV file the corresponding field is "" and I would like put a blank string into the Oracle table when that happens.
This is my control file:
LOAD DATA
infile 'F:\tar.csv'
REPLACE
INTO TABLE tar
fields terminated by ',' optionally enclosed by '"'
TRAILING NULLCOLS
(IDTAR ,
DATABACKUP DATE "YYYY-MM-DD",
PAESE ,
R_ELEM NULLIF (R_ELEM=BLANKS))
and this is the error in the log file:
ORA-01400: cannot insert NULL into ("MY_SCHEMA"."TAR"."PAESE")
How can I avoid the error by supplying a different value?

Answer 1

You can apply an SQL operator, such as NVL(:PAESE, 'XXX'). Notice the colon before the reference to the field name. In situ:
LOAD DATA
infile 'gian.csv'
REPLACE
INTO TABLE tar
fields terminated by ',' optionally enclosed by '"'
TRAILING NULLCOLS
(
IDTAR,
DATABACKUP DATE "YYYY-MM-DD",
PAESE "NVL(:PAESE, 'XXX')",
R_ELEM NULLIF (R_ELEM=BLANKS)
)
With a dummy table:
create table tar (
idtar number,
databackup date,
paese varchar2(10) not null,
r_elem varchar2(10)
);
and CSV, where the 3rd and 4th lines have trailing spaces for the nullif() clause:
1,2017-08-01,A,B
2,2017-08-02,C,
3,2017-08-03,,
4,2017-08-04,"",
then running with that control file gets:
SQL*Loader: Release 11.2.0.4.0 - Production on Fri Aug 4 19:39:23 2017
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Commit point reached - logical record count 4
and the log says:
...
Column Name Position Len Term Encl Datatype
------------------------------ ---------- ----- ---- ---- ---------------------
IDTAR FIRST * , O(") CHARACTER
DATABACKUP NEXT * , O(") DATE YYYY-MM-DD
PAESE NEXT * , O(") CHARACTER
SQL string for column : "NVL(:PAESE, 'XXX')"
R_ELEM NEXT * , O(") CHARACTER
NULL if R_ELEM = BLANKS
Table TAR:
4 Rows successfully loaded.
0 Rows not loaded due to data errors.
0 Rows not loaded because all WHEN clauses were failed.
0 Rows not loaded because all fields were null.
...
Querying the table shows all four rows were loaded:
set null "<null>"
select * from tar;
IDTAR DATABACKU PAESE R_ELEM
---------- --------- ---------- ----------
1 01-AUG-17 A B
2 02-AUG-17 C <null>
3 03-AUG-17 XXX <null>
4 04-AUG-17 XXX <null>
Obviously replace 'XXX' with the actual default string you want to use. You said 'a blank string', so you could use "NVL(:PAESE, ' ')" to insert a single space character for instance. You can't use an empty string though, as that is the same as null as far as Oracle is concerned.