Distribute DB2/400 Relative Record Number (RRN) fields - connect_cdc_mimix_share - 5.8

Connect CDC System Reference Guide

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Connect > Connect CDC (MIMIX Share)
Product name
Connect CDC
Connect CDC System Reference Guide
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A Relative Record Number field in a DB2/400 table is an internally-assigned, zone decimal, number that uniquely identifies a row. The RRN field value cannot be directly updated by a user, nor can it be specified in the column definition list when creating a table. However, such a field can conveniently be used as the unique key required for Connect CDC replication and copy.

You can select an RRN field as a source column, but not as a target column (because an RRN field cannot be updated). Connect CDC uses the DB2/400 RRN function call to retrieve the unique row value, and the Connect CDC Director assigns a datatype of NUMERIC(10) for RRN columns.

Note: Whatever column name you choose for the RRN field, whether it's source or target, is reserved and cannot be a real column name in either table of the mapping

To use an RRN field in Connect CDC distribution: You must specify a parameter (AS400RRN) in the [Director] section of the OmniRep40x\director\omnient.ini file on your Connect CDC Director host machine. For example:


The parameter value you specify (RRN_FIELD_DATA, above) is the name that Connect CDC Director displays for the RRN column. For example, you could you specify RRN_FIELD_MYTEST_DATA as the parameter value for AS400RRN.

Note: If you specify 1 as the parameter value, the RRN column name appears as RRN_FIELD. If you specify 0 as the parameter value, no RRN column is generated, and any column previously generated is removed.

Once the feature is enabled, the Connect CDC Director makes the RRN column available for mapping, and it verifies whether the datatype of the target column to which you map the RRN column is compatible with NUMERIC.

The extracted RRN value gets padded with leading zeros to a length of 10 (133 becomes 0000000133, for example).

Note: If you change the value of the "AS400RRN" then the Director needs to be restarted and the tables needs to be refreshed. If there are tables in "Sending tables" then the RRN column should be remapped.

No other special user actions are required to use this feature, except for the procedures described below in the event of a file reorganization of an Connect CDC source table containing a mapped RRN column.