Oracle SQL Performance Tuning

Composite / Concatenated SQL Indexes

When a single index has multiple columns that are indexed, it is called a composite or concatenated index. Prior to the introduction of skip-scan functionality, queries could only use the index if the leading column of the index was used in the WHERE clause. Consider the example in the following listing where the EMP table has a concatenated index on Empno, Ename, and Deptno. Note that Empno is the first part, Ename is the second…

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Adding line endings to a string

Here’s some PeopleCode I wrote that will add a carriage return and line feed to the end of a String if it is not empty:

or as a method:

Note: This assumes that you want Windows line endings. Typically unix line endings just have a single line feed (Char(10) with no carriage return.

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Network Issues

winsock reset?

A colleague was having trouble with his Windows XP network connection on his Dell laptop after coming back from China. He was able to access the local intranet at work but could not access the internet. I’d never experienced this before. We tried the usual sorts of commands to renew the ip (eg. ipconfig /release and ipconfig /renew). None of these would work. Even after re-installing windows he still wasn’t able to connect to the…

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