Slony is a widespread tool used to replicate PostgreSQL databases at a logical level. In contrast to transaction log shipping, it can be used to replicate instances between various versions of PostgreSQL, and there is no need to replicate an entire instance. It allows us to flexibly replicate individual objects.

In the next chapter, we will focus our attention on SkyTools, a viable alternative to Slony. We will cover installation, generic queues, and replication.