DB2 FOR LUW / DB2FORLUW / A50 - DB2

You have created a .NET Entity Framework project that retrieves 
some data from an Informix IDS database and involves tables 
having columns of type CLOB or BLOB.  In some cases the data 
retrieval operation fails with an exception similar to 
 
IBM.Data.DB2.DB2Exception (0x80004005): ERROR [IX000] 
[IBM][IDS/NT64] Corresponding column types must be compatible 
for each UNION statement. 
   at IBM.Data.DB2.DB2Command.ExecuteReaderObject 
   at IBM.Data.DB2.DB2Command.ExecuteReaderObject 
   at IBM.Data.DB2.DB2Command.ExecuteReader 
   at IBM.Data.DB2.DB2Command.ExecuteDbDataReader 
   at System.Data.Common.DbCommand.ExecuteReader 
   at 
System.Data.EntityClient.EntityCommandDefinition.ExecuteStoreCom 
mands 
 
as a consequence of an error -308 returned by IDS. This error is 
returned in a range of situations and in the case of this APAR 
it is caused by a cast operation problem where, in some parts of 
a query involving UNIONs, CLOB is cast as VARCHAR(255) or BLOB 
is cast to BYTE as shown in the following SQL fragment: 
 
(...) 
      SELECT 
           Extent1.id AS id, 
           Extent1.image AS image,              -- this is a 
BLOB column 
           CAST(NULL AS varchar(255)) AS C2,     -- ERR: should 
be cast as CLOB 
       FROM "informix".myelements_blob AS Extent1 
 
       UNION ALL 
 
       SELECT 
            Extent2.id AS id, 
            CAST(NULL AS byte) AS C2,        --ERR: should be 
cast as BLOB 
            Extent2.novel AS novel,         -- this is a CLOB 
column 
       FROM  "informix".myelements_clob AS Extent2 
(...)

**************************************************************** 
* USERS AFFECTED:                                              * 
* ALL                                                          * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to DB2 Version 10.5 Fix Pack 4.                      * 
****************************************************************

DB2 Cancun Release 10.5.0.4 (also known as Fix Pack 4) for Linux, UNIX, and Windows
 DB2 Version 10.5 Fix Pack 9 for Linux, UNIX, and Windows
 

First fixed in DB2 Version 10.5 Fix Pack 4.

not known / see Local fix

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

21.08.2013
09.09.2014
09.09.2014