Data Recovery in HANA, TimesTen, and SQLFire

There is a persistent myth, like a persistent cough, that claims that in-memory databases lose data when a hardware failure takes down a node because memory is volatile and non-persistent. This myth is marketing, not architecture. Most RDBMS products: including Oracle, TimesTen, and HANA; have three layers where data exists: in-memory (think SGA for Oracle), in…

SQLFire, Exalytics, TimesTen, and HANA… a quick comparison

As you may have noticed I’m looking at in-memory databases (IMDB) these days… Here are some quick architectural observations on VMWare‘s SQLFire, Oracle’s Exalytics and TimesTen offerings, and SAP HANA. It is worth noting up front that I am looking to see how these products might be used to build a generalized data mart or…

Cloud Computing and Data Warehousing: Part 4 – IMDB Data Warehouse in a Cloud

In the previous blogs on this topic (Part 1, Part 2, Part 3) I suggested that: Shared-nothing is required for an EDW, An EDW is not usually under-utilized, There are difficulties in re-distributing sharded, shared-nothing data to provide elasticity, and A SAN cannot provide the same IO bandwidth per server as JBOD… nor hit the…