Requests for data in XML columns by earlier DB2 clients

If you retrieve data from an XML column to a client that is at an earlier release than DB2® 9, your database client cannot handle XML data.

During DRDA processing, when the database server recognizes a client that cannot support XML data, by default, the DB2 database server describes XML data values as BLOB values and sends the data to the client as BLOB data. The BLOB data is the textual XML representation of the XML data, with a complete XML declaration.

If you want to receive the data as a CLOB or DBCLOB data type, instead of a BLOB data type, you can invoke the XMLSERIALIZE function on the column data to instruct the DB2 database server to convert the data to the specified data type before it sends the data to the client.

When you do not invoke XMLSERIALIZE to retrieve data from a database server to a client at an earlier release level, the column from which you retrieve the data does not behave exactly like a BLOB column. For example, although you can use the LIKE predicate on a BLOB column, you cannot use the LIKE predicate on an XML column that returns BLOB data.