A Deep Dive in How Slow SELECT * is
The Backend Engineering Show with Hussein Nasser
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The Importance of Index Only Scans
The data structure is different now, but the content is still pages, you're reading pages. So as I'm scanning the index, and again, scanning the index is going through the B trees,. The layers store these keys, and the keys are stored in pages, and the pages are stored in this very similar thing. And because the value of the secondary index in the leaf page is the primary key, right? Again, this is a same ic call, right? Or Oracle if you have an index organized table, right? Then you technically have the ID, because they say the ID is the primarykey, right? You have the ID right there in the leafpage, in the
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