I have the jar and I restarted Splunk
$ ls -1 /opt/splunk/etc/apps/dbx/bin/lib/ojdbc*
/opt/splunk/etc/apps/dbx/bin/lib/ojdbc5dms.jar
/opt/splunk/etc/apps/dbx/bin/lib/ojdbc5.jar
/opt/splunk/etc/apps/dbx/bin/lib/ojdbc6dms.jar
/opt/splunk/etc/apps/dbx/bin/lib/ojdbc6.jar
From the "Recent DB Connect errors" search, I found this
11:35:36.712 dbx4539:ERROR:BridgeSession - Exception occured while executing command: java.lang.NoClassDefFoundError: Could not initialize class oracle.jdbc.driver.DMSFactory
java.lang.NoClassDefFoundError: Could not initialize class oracle.jdbc.driver.DMSFactory
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