How to Create a SQL Server Linked Server to Oracle 26ai Free
Easily move data from SQL Server to Oracle 26ai Free with this step-by-step guide.
2026-01-26
Oracle
Oracle Performance Tuning: Practical Techniques Every DBA Should Master
Here are a few things every Oracle DBA should know about performance in their databases.
2025-10-03
2,419 reads
Oracle Architecture Overview
In this document I will share an overview of Oracle’s architecture that isn’t complete, but it will give you a basic understanding of how the architecture works, especially if you are coming from other database platforms.
2025-01-24
SQL Server vs Oracle Query Statistics to Improve Performance
In this article, learn how to query cached query statistics and execution plans for Oracle or SQL Server to identify code that can be optimized to improve performance.
2023-07-21
The SELECT Statement in Oracle
The SELECT statement is used to retrieve information from a database. Following the execution of a SELECT statement, a tabular result is held in a result table (called a result set). It allows you to select the table columns depending on a set of criteria. In this article, I will introduce the basic SELECT statement fetching data from just one table.
2023-06-21
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
Why your PL/SQL needs to be testable – and how to do it: Part 1
Part 1: What is testable code, why is it important, and first glimpses on practices that can help
2022-04-27
Oracle subquery caching and subquery pushing
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
The effects of NULL with NOT IN on Oracle transformations
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
Oracle ASM: Migrating from UDEV devices to the ASM Filter Driver
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
4,748 reads
Blogs
A Last Minute Trip to the EU
By Steve Jones
My life has some crazy travel stretches for sure. Between speaking, office visits, customer...
Part 3 of 3: Tuning DiskANN — R, Alpha, L, Beam Width, Recall and Latency
In Part 1, we saw how ‘Vamana’ represents vectors as nodes, connects them with...
Automated SQL Server Benchmarking with HammerDB and Docker: A Complete Testing Framework
I’m excited to announce the release of a new open-source project that fully automates...
Forums
Server-Level Table sizes
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Optional Parameter Plan Optimization in SQL Server 2025: Fixing the Kitchen-Sink Search Procedure
Comments posted to this topic are about the item Optional Parameter Plan Optimization in...
Question of the Day
ORDER BY alias
There is a table tmp_tab:
CREATE TABLE tmp_tab ( id int, val int );
INSERT INTO tmp_tab VALUES (1, 1), (2, NULL), (3, 3), (4, 4), (5, 5);You want to order the rows ids by the following expression:
ISNULL(val, id) + 1Which of the following queries produces the expected ordering and why? (Select all correct) See possible answers