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Delayed Application of Redos on the Standby Side

It may not be required to apply Redos to the Standby side immediately. In this case, the DelayMins in the Broker and the Delay parameter in the LOG_ARCHOVE_DEST_n are set and the Redos are applied late to the Standby side.

LET’S TEST

1. The parameter is updated in the database where Redos are requested to be applied after a certain delay.

2. When the parameter is updated, the LOGs that fall into ALERT LOGs are as follows.

[Physical]—–>ALERT LOG
Thus, we can see what the RFS process is that meets the Redos on the standby side.
3. Tests are passed. A table belonging to the user TEST is deleted. First, the user’s existing tables are queried.
4. We DROP one of the tables.
Even if we wait a few minutes, the Physical Standby shows that the table is not DROP. The reason is that Real-Time APPLY is disabled. Archive Apply is activated.

5. By performing the Log Switch operation, Redo, which hosts the DROP operation, is transferred to the Stanbdy side.

[Physical]—–>ALERT LOG

6. After 1 minute, we check if the table is DROP.

[Physical]—–>ALERT LOG

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