How to resolve the encoding problem while migration from informix9.4

Question

When I migrate the informix9.4 database, there occur a error while migrate the data from informix to oracle.
Because the source tables has a column which type is "vchar", the some row's data length more the 4000, so migration workbench convert this column type from "vchar" to "clob" automaticly. But when the worbench has created the oracle model, and then migrate the data, there occured this error:
java.io.UnsupportedEncodingException: ISO2022CN_GB
java.sql.SQLException: index miss IN or OUT param:: 9
+     at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:125)+
+     at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:162)+
+     at oracle.jdbc.driver.OraclePreparedStatement.processCompletedBindRow(OraclePreparedStatement.java:1536)+
+     at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:2900)+
+     at oracle.jdbc.driver.OraclePreparedStatement.execute(OraclePreparedStatement.java:2996)+
+     at oracle.mtg.migrationServer.LoadTableData._migrateTableData(LoadTableData.java:1473)+
+     at oracle.mtg.migrationServer.LoadTableData.run(LoadTableData.java:326)+
+     at oracle.mtg.migration.WorkerThread.run(Worker.java:268)+
The encode in the source informix database is "zh_CN.gbk", and the encode in the destination database is "zh_CN.gbk", why this prompt the convert error?
Another information is that excluding this table, other tables can migrated success.
So, I guess this problem must has association with the type conversation which from "vchar" to "clob", can anyone help me with this, Thanks.

Answer 1

Hello,
well, the limit of 4000 is clear. From the Oracle® Migration Workbench Reference Guide for Informix Dynamic Server Migrations:
VARCHAR(m,r)
The Informix Dynamic Server VARCHAR data type stores varying length single-byte and multibyte character strings of letters, numbers. and symbols. The maximum size of this column is m, that can range from 1 to 255. The minimum reserved space is r. This is optional and defaults to 0 if not specified. The minimum reserved space can range from 0 to 255.
The comparable Oracle data type is VARCHAR2(n) that also stores variable-length character strings. An Oracle VARCHAR2(n), however, can have a maximum string length of between 1 and 4000 specified for n.
Specifying a minimum reserved space is useful if the data in a row is initially small but is expected to grow at a later date. If this is the case then, when migrating Informix Dynamic Server tables that contain VARCHAR columns consider increasing the PCTFREE value in the storage clause for these tables in the Oracle database. If this column is used in an index, then the PCTFREE values for the corresponding index storage should also be considered. For indexes based on VARCHAR columns, Informix Dynamic Server allocates the maximum storage.
So it is not surprising that the workbench is converting a VARCHAR with a length of more than 4000 to a CLOB.
But that does not explain the encoding exception. This might be a problem of the Informix JDBC driver.
Is the Informix JDBC Driver Programmer's Guide helpful for you: http://publibfi.boulder.ibm.com/epubs/pdf/6435.pdf
Can you reproduce the problem with a Java program against your Informix database using your Informix JDBC driver?
Which version of Informix JDBC driver are you using?
Best regards
Wolfgang