I have several independant system and I want to carry out data and system integration. I know there are 3 methods: vertical integration (silos), star integration (spaghetti) and horizontal integration (bus). But I don't understand them clearly. Can anyone please explain more and maybe give me some samples? Thanks.
How do you "know" there are three methods of data integration. You must have gotten those buzzwords from some book or site.
Honestly, we deal more with practical matters here. We're not a buzzword dictionary. If you explain that nature of your business, your systems, and what you are trying to accomplish, we can help point you in the right direction.
Are you considering creating a datawarehouse, or actually consolidating your OLTP systems?
If it's not practically useful, then it's practically useless.