CST 363 Week 5 Learning Journal

If indexes are supposed to speed up performance of query,  what does the author mean by a slow index? 

The author means that although indexes are supposed to speed up queries, there are times index lookups can be slow. The index isn't broken but the index is not being used properly. For example, If there are multiple entries in a tree, traversing it can take much longer if there are duplicates. A "slow index" means that even with an index, the query can be slow due to the amount of data that still needs to be read like in matching rows or scattered table data.

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