I was reading a blog earlier on this evening that was talking about the definitions of “consistent gets” and “db block gets”. The point of the article was that it’s very hard to find good descriptions of exactly what these two terms mean.
I’ll add the link to the blog item (and give my definitions) in a few days time but, in the interim, does anyone want to try their hand at defining these two very common terms in a couple of short paragraphs.
[Updated: 11th June] Just a brief note to tantalize a little more, did you know that :
- You can visit blocks in the buffer cache without recording a consistent get or a db block get.
- You can CHANGE the current version of a block without recording a db block get (or even a consistent get – and without generating undo or redo).
- Consistent gets can create versions of a block that have NEVER, EVER, existed at any point in time (or, much the same thing, at any SCN).