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MDTransform - Data Copy for Remote Tables containing LOB Columns

For most tables located on a different partition, MDTransform uses DDM to copy the data to the target partition. However, Db2 for IBM i does not allow the query of records over DDM when a remote table contains Large Object (LOB) columns.

How MDTransform Handles Remote LOB Tables

When a Data Copy Template includes a remote table containing LOB columns, MDTransform will perform the following steps instead:

Target Partition: 1. Invoke MDCMS procedure MDSENDFILE on the remote partition with the information needed to send the LOB table to the target partition

Remote Partition: 1. Save while active of the LOB table into a save file 2. Copy the save file to the IFS 3. Use the FTP or MDFTP definition for the target partition to transfer the IFS file to the target partition using FTP, FTPS or SFTP 4. remove the save file and IFS file

Target Partition: 1. copy the IFS file into a save file 2. create a temporary library to hold the LOB table 3. restore the saved table into the temporary library 4. remove the save file and IFS file 5. execute the data copy locally, including any conditions and transformations 6. remove the temporary library

Prerequisites on Remote Partition for use of MDSENDFILE

  1. MDCMS must be installed and a valid MDCMS *CORE license must be present. An MDTransform license isn't required.
  2. The DDM user defined for connecting to the remote partition must have *USE authority to the MDCMS product library
  3. An IBMi Location definition for the target partition must exist in MDCMS on the remote partition
  4. The Location definition must use the Distribution Method of FTP (IBM FTP or secure FTP) or MDF (MDFTP for FTP, FTPS or SFTP)