Tales From A Lazy Fat DBA

Hi Guys,

Last week someone from my team contacted me for a problem that he was facing with the Golden Gate, he was getting an error message with replicat process saying ‘Error mapping TEST.TABLE1 to TEST.TABLE1’ and the replicat process is abending at the target end. He was using Golden Gate version 12.1.2.0. Now during the initial investigation we found the table structure both at the source and target is same except column order/positions, just like below.

Source
-----------------------
    TEST.TABLE1
ID Varchar2(10)
Name Varchar2(10)
Codes Numeric(10)

Target:
------------------------
    TEST.TABLE1
ID Varchar2(10)
Codes Numeric(10)
Name Varchar2(10)

As GG works with the column order and not explicitly with the column names, it lead to that error at the target while doing the INSERTS in to the table. We knew that this is now auto handled by the GG, but not sure on the version when it got fixed, so immediately, we started looking for newer releases and their documentations, and luckily we found release notes for Golden Gate 12.2 which clearly explained that now there isn’t any need to generate the DEFGEN files, or to use ASSUMETARGETDEFS or SOURCEDEFS parameter (in some cases).

Starting from Golden Gate version 12.2 (released in year 2016), the trail files now contains the metadata (TDR or table definition records), so GG knows table details like column order/positions, data type, column length etc. before applying the changes to the table. So, now even if you add a new table, drop a column, add a new column, rename an existing column, change column datatype length, you don’t need to worry as Golden Gate will take care by its own.

So, about the solution, we had two options to choose from – Upgrade GG from 12.1 to 12.2 or else use FORMAT RELEASE 12.2 parameter, with that, there is no need to use any of the above mentioned parameters. We choose to upgraded GG version to 12.2 and that fixed the problem!

Hope It Helped
Prashant Dixit