Include in your journal entry for this week the following
The web site "Use the Index Luke" has a page on "slow indexes". https://use-the-index-luke.com/sql/anatomy/slow-indexesLinks to an external site.
If indexes are supposed to speed up performance of query, what does the author mean by a slow index?
While indexes are generally used to speed up the performance of database queries, there are cases where they don't work as efficiently as expected. Markus Winand explains that a "slow index" occurs when the database has to follow a chain of leaf nodes continuously checking for matching entries, and also access the table. These steps may involve accessing many blocks, which can slow down the query rather than improve its performance.
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