December 2016

Why oh Why Do We Still Not Have a Fast Bulk “SQL*Unloader” Facility?

Way back in 2004 I was working at the UK side of the Human Genome project. We were creating a massive store of DNA sequences in an Oracle database (this was one of two world-wide available stores of this information, for free & open use by anyone {* see note!}). The database was, for back then, enormous at 5-6TB. And we knew it would approx double every 12 months (and it did, it was 28TB when I had to migrate it to Oracle 10 in 2006, over 40TB 6 months later and grew to half a petabyte before it was moved to another organisation). And were contemplating storing similar massive volumes in Oracle – Protein, RNA and other sequence stores, huge numbers of cytological images (sorry, microscope slides).

How Partial Indexing helps you save space in #Oracle 12c

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Over time certain partitions may become less popular. In 12c, you don’t have to index these partitions anymore! This can save huge amounts of space and is one of the best 12c New Features in my opinion. Really a big deal if you are working with range partitioned tables where the phenomenon of old ranges becoming unpopular is very common. Let’s have a look, first at the problem: