6.23.3 Points to consider about locking during concurrent command execution
When an HADB server executes the commands listed in 6.23 Points to consider when executing commands concurrently, it reserves locked resources according to 2.10.4 Locked resources that are reserved and their lock modes.
When you execute multiple commands concurrently, make sure that no contention occurs during the process of locked resource reservation. If contention occurs during the process of locked resource reservation, an error normally occurs (the KFAA50290-E message is output).
However, there are some exceptions (cases in which the transaction waits until a locked resource can be reserved without causing an error). For details, see 2.10.4 Locked resources that are reserved and their lock modes.