Selecting the server default character set

When you configure your server, you are asked to specify a default character set for the server. The default character set is the character set in which the server stores and manipulates data. Each server can have only one default character set.

By default, the installation tool assumes that the native character set of the platform operating system is the server’s default character set. However, you can select any character set supported by Adaptive Server as the default on your server (see Table 7-1).

For example, if you are installing the server on IBM RS/6000 running AIX, and you select one of the Western European languages to install, the installation tool assumes the default character set to be ISO 8859-1.

If you are installing a Unicode server, select UTF–8 as your default character set.

For non-Unicode servers, determine what platform most of your client systems use and use the character set for this platform as the default character set on the server.

This has two advantages:

For example, if most of your clients use CP850, specify CP850 on your server. You can do this even if your server is on an HP-UX system (where its native character set for the Group 1 languages is ROMAN8).

NoteSybase strongly recommends that you decide which character set you want to use as your default before you create any databases or make any changes to the Sybase-supplied databases.

In the example below in Figure 7-2, 175 clients all access the same Adaptive Server. The clients are on different platforms and use different character sets. The critical factor that allows these clients to function together is that all of the character sets in the client/server system belong to the same language group (see Table 7-1). Notice that the default language for the Adaptive Server is CP 850, which is the character set used by the largest number of clients. This allows the server to operate most efficiently, with the least amount of character set conversion.

Figure 7-2: Clients using different character sets in the same language group

To help you choose the default character set for your server, the following tables list the most commonly used character sets by platform and language.

Table 7-2: Popular Western European client platforms

Platform

Language

Character set

Win 95, 98

U.S. English, Western Europe

CP 1252

Win NT 4.0

U.S. English, Western Europe

CP 1252

Win 2000

U.S. English, Western Europe

CP 1252

Sun Solaris

U.S. English, Western Europe

ISO 8859-1

HP-UX 10,11

U.S. English, Western Europe

ISO 8859-1

IBM AIX 4.x

U.S. English, Western Europe

ISO 8859-1

Table 7-3: Popular Japanese client platforms

Platform

Language

Character set

Win 95, 98

Japanese

CP 932 for Windows

Win NT 4.0

Japanese

CP 932 for Windows

Win 2000

Japanese

CP 932 for Windows

Sun Solaris

Japanese

EUC-JIS

HP-UX 10,11

Japanese

EUC-JIS

IBM AIX 4.x

Japanese

EUC-JIS

Table 7-4: Popular Chinese client platforms

Platform

Language

Character set

Win 95, 98

Chinese (simplified)

CP 936 for Windows

Win NT 4.0

Chinese (simplified)

CP 936 for Windows

Win 2000

Chinese (simplified)

CP 936 for Windows

Sun Solaris

Chinese (simplified)

EUC-GB

HP-UX 10,11

Chinese (simplified)

EUC-GBS

IBM AIX 4.x

Chinese (simplified)

EUC-GB