DB2 FOR LUW / DB2FORLUW / A50 - DB2

SYSIBM.TO_NCHAR returns different result in v9.7 vs v10.5 when
using UNION.

Repro Scenario:
CREATE DATABASE TEST USING CODESET UTF-8 TERRITORY US;
CREATE TABLE test100(col1 INT,col2 TIMESTAMP);
CREATE TABLE test200(col1 INT,col2 TIMESTAMP);

INSERT INTO test100 values(1,CURRENT date);
INSERT INTO test200 values(1,CURRENT date+1 day);
INSERT INTO test200 values(2,NULL);

v9.7 Results

SELECT col1,To_nchar(CAST(col2 AS TIMESTAMP), 'mm/dd/yyyy') FROM
test100 UNION SELECT col1,To_nchar(CAST(col2 AS TIMESTAMP),
'mm/dd/yyyy') FROM test200

COL1        2
----------- -----------
          1 05/25/2018
          1 05/26/2018
          2 -

v10.5 Results

SELECT col1,To_nchar(CAST(col2 AS TIMESTAMP), 'mm/dd/yyyy') FROM
test100 UNION SELECT col1,To_nchar(CAST(col2 AS TIMESTAMP),
'mm/dd/yyyy') FROM test200

COL1        2
----------- -----------
          1 05/25/2018
          1 05/26/2018
          2 05/26/2018

****************************************************************
* USERS AFFECTED:                                              *
* ALL                                                          *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* See Error Description                                        *
****************************************************************
* RECOMMENDATION:                                              *
* Upgrade DB2 server to v10.5 Fixpack 10                       *
****************************************************************

Replace TO_NCHAR(...) with NVARCHAR(TO_CHAR(...))

See LOCAL FIX

forerunner  : 
follow-up : IT25368 

Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :

29.05.2018
16.07.2018
16.07.2018