JDBC driver versions
If you get undefinably issues: Please check, if you use the correct driver that is shipped with the version from your DB2 server. DB2 is here a little bit pedantic and the client JDBC driver should match the server version.
There was also a change in the usage of getColumnLabel and getColumnName in the JDBC drivers version 4.0 and later.
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SELECT column AS aliasName from table
With JDBC drivers version 4.0 and later you will most likely not get the aliasName.
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