For Microsoft Windows users, the issue is complicated because there are at least two code pages in use on most PCs. This issue affects both Windows clients and servers.
MS-DOS, as well as character-mode applications (those using the console or “DOS box”) in Windows, use code pages taken from the IBM set. These are called OEM code pages (Original Equipment Manufacturer) for historical reasons.
Windows operating systems do not require the line drawing characters that were held in the extended characters of the OEM code pages, so they use a different set of code pages. These pages are based on the ANSI standard and are therefore commonly called ANSI code pages.
Sybase IQ supports collations based on both OEM and ANSI code pages.
Consider the following situation:
A PC is running the Windows 98 operating system with ANSI code page 1252.
The code page for character-mode applications is OEM code page 437.
Text is held in a database created using the collation corresponding to OEM code page 850.
An uppercase A grave in the database is stored as character 183. This value is displayed as a graphical character in a character-mode application. The same character is displayed as a dot in a Windows application.
For information about choosing a single-byte collation for your database, see “Understanding collations”.
