Question

I have two tables of data for example:

Network Status

ipaddress       time       violation
192.168.1.1     2:00       yes
192.168.1.6     2:00       no
192.168.1.11    2:00       no
192.168.1.1     3:00       no
192.168.1.6     3:00       no
192.168.1.11    3:00       yes

and

Firewall Log

ipaddress       machinetype    location
192.168.1.1     computer       London
192.168.1.6     server         New York
192.168.1.11    server         Bejing

and I wish to merge the data from Firewall Log into the Network Status table so I will have the following:

Network Status

ipaddress       time       violation       machinetype       location
192.168.1.1     2:00       yes             computer          London
192.168.1.6     2:00       no              server            New York
192.168.1.11    2:00       no              server            Bejing
192.168.1.1     3:00       no              computer          London
192.168.1.6     3:00       no              server            New York
192.168.1.11    3:00       yes             server            Bejing

Does anyone have any ideas? I assumed there would be a command to merge tables by a specific column value but after research I have only come across the join and select into commands. But I can’t figure out how to use these to achieve what I want.

Thanks!

Answer 1

To “merge” this tables you need:

1) Add “machinetype” and “location” columns to the “Network Status” table:

ALTER TABLE "Network Status"
  ADD COLUMN "machinetype" TEXT;
ALTER TABLE "Network Status"
  ADD COLUMN "location" TEXT;

2) Populate them with data

UPDATE "Network Status" NS
SET "machinetype" = FL."machinetype",
    "location" = FL."location"
FROM "Firewall Log" FL
WHERE FL."ipaddress" = NS."ipaddress"

Or you can create a VIEW and use it to SELECT data as if it is a table:

CREATE VIEW "Status and log" AS
SELECT NS."ipaddress", NS."time", NS."violation", FL."machinetype", FL."location"
FROM "Network Status" NS
JOIN "Firewall Log" FL ON FL."ipaddress" = NS."ipaddress"