I remember the theory, you'd have a line for each subnet. and each port/interface of the router corresponds to a subnet. infact each port has an IP on its subnet.
the router has one routing table, with each row for each subnet. and each associated port/interface.
a row of the routing table might say 192.168.0.0/24 (i.e. it includes 192.168.0.4) and there's an interface 192.168.0.1 and the interface may be called Eth0
Any packet sent to the router, whichever port it comes in on, if it has an IP on 192.168.0.0/24 will end up going out on Eth0.
The router looks at the destination ip of the incoming packet sees it 192.168.0.4 sees that is on subnet 192.168.0.0/24 and looks through its routing table and sends it out Eth0.
Whether networks connected to the router are private IPs or public IPs is irrelevant.
A contrast between that router and a NAT Modem Router, is that the NAT Modem Router at home is like a 2 port machine, with a switch at the local side and you can't connect multiple local networks to it. Whereas a proper router has no switch in it and has more than 2 ports and you can configure subnets on the various ports.
If you read about Routing, I think you'd find that it only describes it like that, it make no distinctions as you do between industrial routers or not, local networks or not, there are no distinctions. And they all have one routing table. Not sure where you got the idea they'd have more than one. The only point i'd make though is that which is in the paragraph above, about some home routers having in built switches. But one tends not to read that in articles on Routing.