Just finished running log miner on a development database and found that SQL_REDO column had an invalid SQL statement containing HEXTORAW values
INSERT INTO HR.EMPLOYEES(col#1, col#2) values (hextoraw('69i57j33i22i29i30'),hextoraw('a108944'));"Generally, the SQL_REDO column contains an SQL statement that allows you to revert any query. For example, for an INSERT statement, SQL_REDO will contain DELETE statement. For a DELETE statement, SQL_REDO will contain INSERT statement.
Basically, you can rollback by running the query under SQL_REDO column. But in my case, I got an invalid INSERT statement (against a delete statement) with some HEXTORAW values.
Problem: I just cannot run it directly against the database 😞
After a quick research found out that if the table is altered, the Log Miner does not know about the previous table structure.
And hence, Log Miner cannot re-construct any SQL statements that were executed on the previous table structure. This is the reason why we see non-executable SQL which includes HEXTORAW formats!