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Considerations and recommendations > DB2 Recovery Expert works one row at a tim... - Pg. 116

the column. This causes a problem when log analysis generates INSERTs in undo SQL for a table with a GENERATED ALWAYS column. The undo SQL cannot use specific values in the GENERATED ALWAYS column, so it has to use DEFAULT as the value. This means that, when you recover a table with a GENERATED ALWAYS column using redo or undo SQL that contains INSERTs, the values inserted into the GENERATED ALWAYS column might not be the same as the original values. This is unavoidable due to the design of GENERATED ALWAYS columns. 5.7.6 DB2 Recovery Expert can quiesce the table space When you run the Log Analysis tool using backward update reconstruction (see 5.7.4, "Masked update reconstruction" on page 115), DB2 RE quiesces the table space at the point when you generate a detailed report or redo or undo SQL. For the DB2 RE GUI, this is the point at which you double-click a transaction in the Log Analysis Transactions window (see Figure 5-13 on page 96) or select whether to produce undo or redo SQL (see Figure 5-14 on page 96). For the db2la command, this is the second iteration of the command, where you use the -D option. The quiesce is required because DB2 RE needs to access the current table data to reconstruct updates, and it is important that data is not changed by users during this process.