Supported Data Sources

Models can initialize the input data entities from any supported source, with some caveats.

The default security restrictions for xprmsrv are pre-configured to allow Xpress Insight to connect to external databases but not to external files.
Xpress Insight allows trusted file locations to be white-listed as accessible from the executing Mosel model. The white-lists for read, read-write, and execute permissions can be edited in the execution worker configuration file (c:\xpressmp\bin\xprmsrv.cfg by default). The worker must be restarted for changes to take effect.
Some ODBC drivers do not behave correctly with relative paths and so attempts to access model resource files that are locally referenced may fail. In this case, the workdir parameter can be used to get the absolute path to the current working directory. For example:
```
SQLconnect('DRIVER=Microsoft Access Driver (*.mdb);dbq=' + getparam("workdir")+"\\"+AccessFile)
```
Microsoft Excel is not recommended as an ODBC data source. An issue with certain versions of Microsoft^® Windows^® (8 and 2012) means that when xprmsrv is started as a service it may not be able to use the mmodbc.excel driver to access Microsoft Excel as a data source. This can be resolved by using the mmsheet.xslx driver.