April 2006
Intermediate to advanced
640 pages
16h 46m
English
Content preview from Inside Microsoft® SQL Server™ 2005: T-SQL QueryingBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Materialized Path
So far I presented solutions where paths were computed when the code was executed. In the materialized path solution, the paths will be stored so that they need not be computed repeatedly. You basically store an enumerated path and a level for each node of the tree in two additional columns. The solution applies only to trees—possibly forests.
There are two main advantages of this approach over the iterative/recursive approach. Queries are simpler and set-based (without relying on recursive CTEs). Also, queries typically perform much faster, as they can rely on indexing of the path.
However, now that you have two additional attributes in the table, you need to keep them in sync with the tree as it undergoes changes. The cost of ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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