Oracle optimizer removing or coalescing subqueries
The Oracle optimizer often changes the query to get better performance. In this article, Jonathan Lewis explains two more optimizations involving subqueries.
2022-05-25
The Oracle optimizer often changes the query to get better performance. In this article, Jonathan Lewis explains two more optimizations involving subqueries.
2022-05-25
Part 1: What is testable code, why is it important, and first glimpses on practices that can help
2022-04-27
In this article, Jonathan Lewis discusses why you might want to stop the optimizer from unnesting some subqueries and how to control where the optimizer positions each subquery.
2022-04-11
IN and NOT IN subqueries are frequently used in Oracle. Jonathan Lewis explains how the optimizer handles NULL with IN and NOT IN.
2022-03-18
This article looks at the way in which you can convert unmanaged devices to the ASM filter drive in an Oracle system.
2022-03-04
1,690 reads
In this article, we will analyze the various out-of-the-box deployment options Oracle Cloud Infrastructure and Google Cloud Platform offers to host a Microsoft SQL Server database. This information can prove to be handy while deciding on the best cloud provider to host a given application or database.
2022-02-18
5,900 reads
To troubleshoot poorly performing SQL in Oracle, you must understand which transformations the optimizer has made. Jonathan Lewis demonstrates several possible optimizations for one query.
2022-02-09
Oracle added several enhancements to the sequence object in version 12c, including an “identity” column feature. Jonathan Lewis explains how to work with these new features.
2021-09-10
Oracle sequences supply unique numbers that can be used when populating tables. In this article, Jonathan Lewis explains the typical uses of Oracle sequences.
2021-08-04
Using sequences when scaling up with Oracle RAC presents more issues with contention. In this article, Jonathan Lewis explains how to avoid the problems.
2021-05-31
One of the nice things about the Microsoft Connector for Oracle is that it...
By Steve Jones
I get asked questions by salespeople all the time. Usually this is because a...
By Steve Jones
jouska – a hypothetical conversation that you compulsively play out in your head –...
I've noticed in one of our applications a cursor uses operation 40 and that...
Ok, need someone to talk me off the cursor ledge on this one. I...