SQL Developer 1.5.1 - warning messages generated by CREATE TABLE

Question

Hi,
Have an issue with a CREATE TABLE statement - it works correctly, but generates a warning message when used in SQL Developer (1.2 or 1.5.1). Full test case below:
Setup:
drop table samplenames;
drop table customers;
drop table phones;
drop table customers_phone;
drop sequence primkey;
create table samplenames
(name VARCHAR2(10));
insert into samplenames values ('dan');
insert into samplenames values ('joe');
insert into samplenames values ('bob');
insert into samplenames values ('sam');
insert into samplenames values ('weslington');
insert into samplenames values ('sue');
insert into samplenames values ('ann');
insert into samplenames values ('mary');
insert into samplenames values ('pam');
insert into samplenames values ('lucy');
create sequence primkey
start with 1000000
increment by 1;
create table customers as
select primkey.nextval as cust_id,
tmp1.name || tmp2.name as first_name,
tmp3.name || tmp4.name || tmp5.name as last_name
from samplenames tmp1,
samplenames tmp2,
samplenames tmp3,
samplenames tmp4,
samplenames tmp5;
CREATE TABLE PHONES AS
SELECT cust_id, 'H' as phn_loc, trunc(dbms_random.value(100,999)) as area_cde,
trunc(dbms_random.value(1000000,9999999)) as phn_num
FROM customers;
INSERT INTO PHONES
SELECT cust_id, 'B' as phn_loc, trunc(dbms_random.value(100,999)) as area_cde,
trunc(dbms_random.value(1000000,9999999)) as phn_num
FROM customers;
--randomly delete ~10% of records to make sure nulls are handled correctly.
delete from phones
where MOD(area_cde + phn_num, 10) = 0;
create table statement (there are legacy reasons for why this is written the way it is):
CREATE TABLE customers_phone NOLOGGING AS
SELECT cst.*,
piv.HOME_PHONE,
piv.WORK_PHONE
FROM (SELECT cust_id,
MAX(decode(phn_loc, 'H', '(' || area_cde || ') ' ||
substr(phn_num,1,3) || '-' || substr(phn_num,4,4), NULL)) AS HOME_PHONE,
MAX(decode(phn_loc, 'B', '(' || area_cde || ') ' ||
substr(phn_num,1,3) || '-' || substr(phn_num,4,4), NULL)) AS WORK_PHONE
FROM phones phn
WHERE phn_loc IN ('H', 'B')
AND cust_id IS NOT NULL
AND EXISTS (SELECT NULL
FROM customers
WHERE cust_id = phn.cust_id)
GROUP BY cust_id) piv,
customers cst
WHERE cst.cust_id = piv.cust_id (+)
Warning message output:
"Error starting at line 1 in command:
CREATE TABLE customers_phone NOLOGGING AS
SELECT cst.*,
piv.HOME_PHONE,
piv.WORK_PHONE
FROM (SELECT cust_id,
MAX(decode(phn_loc, 'H', '(' || area_cde || ') ' || substr(phn_num,1,3) || '-' || substr(phn_num,4,4), NULL)) AS HOME_PHONE,
MAX(decode(phn_loc, 'B', '(' || area_cde || ') ' || substr(phn_num,1,3) || '-' || substr(phn_num,4,4), NULL)) AS WORK_PHONE
FROM phones phn
WHERE phn_loc IN ('H', 'B')
AND cust_id IS NOT NULL
AND EXISTS (SELECT NULL
FROM customers
WHERE cust_id = phn.cust_id)
GROUP BY cust_id) piv,
customers cst
WHERE cst.cust_id = piv.cust_id (+)
Error report:
SQL Command: CREATE TABLE
Failed: Warning: execution completed with warning"
I am on 10.2.0.3. The CREATE TABLE always completes successfully, but the warning bugs me, and I have had no success tracking it down since there is no associated numberr.
Anyone have any ideas?

Answer 1

Hi ,
The Oracle JDBC driver is returning this warning so I will be logging an issue with them, but for the moment SQL Developer will continue to report the warning as is.
The reason for the warning is not clear or documented as far as I can tell,
but I have replicated the issue with a simpler testcase which makes it easier to have a guess about the issue :)
----START
DROP TABLE sourcetable ;
CREATE TABLE sourcetable(col1 char);
INSERT INTO sourcetable VALUES('M');
DROP TABLE customers_phone;
CREATE TABLE customers_phone AS
SELECT MAX(decode(col1, 'm','OK' , NULL)) COLALIAS
FROM sourcetable;
----END
The warning occurs in the above script in SQL Developer , but not in SQL*Plus.
The warning disappears when we change 'm' to 'M'.
The warning disappears when we change NULL to 'OK2'
In all cases the table creates successfully and the appropriate values inserted.
My gut feeling is ...
During the definition of customers_phone, Oracle has to work out what the COLALIAS datatype is.
When it sees NULL as the only alternative (as sourcetable.col1 = 'M' not 'm') it throws up a warning. It then has to rely on the 'OK' value to define the COLALIAS datatype, even though the 'OK' value wont be inserted as sourcetable.col1 = 'M' and not 'm'. So Oracle makes the correct decision to define the COLALIAS as VARCHAR2(2), but the warning is just to say it had to use the alternative value to define the column.
Why SQL*Plus does not report it and JDBC does, I'm not sure. Either way it doesn't look like a real issue.
Again, this is just a guess and not a fact.
Just though an update was in order.
Regards,
Dermot.