WayneS (5/27/2010)
Question for you Paul:It is stated in BOL:
Instead of constructing a B-tree structure based on a value stored in a particular row, the Full-Text Engine builds an inverted, stacked, compressed index structure based on individual tokens from the text being indexed.
Now, I'm not about to question Kalen, but where MS is stating so specifically that it's not a B-tree, what gives here?
Hey Wayne,
This is just wording again - and it is confusing. My guess is that the intention of the writer was to show that full-text indexes have a different internal arrangement from 'ordinary' indexes. The distinction is between a B+ tree based on a value stored in a particular row, and a B+ tree built on an inverted, stacked, compressed structure build on parsed tokens.
If you have Kalen's 2008 Internals book, the relevant sections are on pages 345-346. A key part (talking about FT indexes) is "...their space usage is tracked in exactly the same way (using IAM pages) and their structures are the same as regular indexes."
As I keep saying, though, whether you consider full-text indexes and 'regular' indexes to have the same structure or not depends a lot on what level of structure we are talking about.
Paul
Paul White
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