D16 Code sets, NLS and character conversion vs. DB2
Roland Schock ARS Computer und Consulting GmbH
05.10.2006 • 11:45 a.m. – 12:45 p.m.
Platform: DB2 for Linux, Unix, Windows
Code sets and character conversion is something, which is usually neglected during database design and usage. Everybody expects it will work correctly without any effort. But practice shows, the true detail and impact is often misunderstood and a few details can help adminstrators and database developers to do the right thing. After some necessary definitions this presentation describes, how you can specify the code page used. You will see what character conversion is and how to avoid common problems. At the end we will shortly discuss performance impacts.
1 Overview
• What are character sets, encoding schemes and code pages? • Where can I define the code page used? • What is code page conversion and where does it happen? • What problems can arise and how can I avoid them? • Performance considerations
2
On the next few slides we will define basic terms frequently used for this topic. The terms are widely used, but often they are only understood partially. In the case of problems it is essential to understand the concepts to deduct the origin of the problem.
2 Character Sets
• Basically a character set is just a collection of entities or graphical symbols with a meaning. • Examples for character sets are the latin alphabet, digits, naval flag signs or other symbols:
A, B, C, ... α γ π ξ ᇹ ぁゆ㌹㌺