There is no #data loss during a switchover. After a switchover, each database continues to participate in the Data Guard configuration with its new role.
00:00 Perform manual switchover
04:10 Switchover configuration
05:31 Check primary and standby for gap
07:15 Convert primary to standby
11:08 Execute query on client
11:22 Convert standby to primary
12:00 Check client query
16:18 Get back to original setup
19:13 Edit TNS entries-example
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