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Considerations and recommendations > Log analysis for tables with LOBs - Pg. 117

Moreover, DB2 logs one entry or LSN for every row which is either deleted, inserted, or updated. There is no information about the original statement that actually caused the change to the row. Therefore, DB2 RE generates undo/redo SQL per row for DELETE and INSERT activity as well. Redo SQL might not be the same For the same reasons as above, the redo SQL might not be the same as original SQL issued by user. Consider this example: db2 delete from VPS.CAR This command deletes all rows in the table, but redo SQL comprises of one delete statement per deleted row. It would produce the same results as long as the state of the table is same as when the original statement was run. 5.7.8 Log analysis for tables with LOBs The process for analyzing tables with LOB data is the same as for tables without LOB data. But remember that DB2 RE can only recover LOB data if it is logged in the first place. With LOB data columns, there is a Not Logged option, which basically means do not log the LOB data. If you are not logging the LOB data, then DB2 RE clearly cannot create report or generate undo or redo SQL for it. There is also a one gigabyte (GB) hard limit per LOB object logged to DB2 log