Exclusive control at the API inventory unit level

①Is it correct to understand that in the following API processes, record locking (exclusive control) is done when performing stock in/out operations?
・ShopFloorConnector.svc/IssueComponentLine
・ShopOrdersHandling.svc/IssueExecute
・Issue_Inventory_Part_SVC.Do_Issue_Inventory_Part
・Receive_Inventory_Part_SVC.Do_Receive_Inventory_Part_In_Update
②If another in/out process runs at the same time as the API execution, will the process that runs later cause an error?
③In the API, how is data being controlled when it comes to handling stock in and out?
→Since access to inventory data happens frequently, it's hard to imagine that the process executed later would fail every time we access the same record, so I'm curious about what kind of control is in place.