OpenEdge Data Management: DataServer for Microsoft SQL Server

MS SQL Server DataServer data source limits
Database design issues
A MS SQL Server data source has upper limits on various components; for example, the number
of columns per table, the number of columns per SELECT statement in a view, the maximum size
of a data row, and the maximum length of character data types. These restrictions might affect
how OpenEdge applications run. See your Microsoft SQL Server documentation for full details.
Code pages
Flexibility in managing code pages, also called character sets, is critical for international
applications. When you access a MS SQL Server data source through the DataServer, the
DataServer retrieves character data as determined by the code page that the data source uses.
For OpenEdge databases, the default code page is iso8859–1; however, the OpenEdge model
allows you to designate code pages for the data source and for the client.
Figure 2–1 shows a possible configuration of code pages for the DataServer components and
processes.
Data
source
Data source
iso_1
Native
data
source
interface
ODBC
Indicates that a
code-page conversion
can occur at this
location
Data
Server
SH
iso8859-1
Figure 2–1: DataServer processes and code pages
GUI monitor
and
keyboard
Client
iso8859-1
In the configuration shown in Figure 2–1, all components use the same code page. The
OpenEdge iso8859–1 code page is a subset of the iso_1 code page used by the default
installation of MS SQL Server. For information on setting character sets for your data source,
see the administration guide supplied by the vendor. On the OpenEdge side, if the client and the
schema holder use different code pages, a conversion takes place between them.
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