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Tag Archives: Performance
I’m often asked what is the best tool for viewing execution plans and for me the answer is always SQL Monitor (included in the Oracle Tuning Pack). It really is the most invaluable tool if you need to determine what … Continue reading
Over the last month or so I’ve been on the road presenting at different user group conferences and meeting with customers. I’ve gotten a number of requests via blog comments to share the slides for the sessions I presented. One … Continue reading
Over the last few years there has been a rapid surge in the adoption of smart devices. Everything from phones and tablets, to smart meters and fitness devices, can connect to the Internet and share data. You only have to … Continue reading
If you are on Exadata or taking advantage of Database In-Memory it’s possible your queries will benefit for the automatically created and maintained Storage Indexes.
But what exactly are Storage Indexes and why don’t I always see a benefit from them?
Let me start by describing what Storage Indexes are in relation to Database In-Memory but remember they behavior in exactly the same way on the Exadata storage cell.
A Storage Index keeps track of minimum and maximum values for each column in an In-Memory Compression Unit (IMCU) or 1MB chunk on the Exadata storage cells. When a query specifies a WHERE clause predicate, the In-Memory Storage Index on the referenced column(s) is examined to determine if any entries with the specified value exist. Continue reading