Because there are so many drivers available for ODBC, you may find that data source error codes don't necessarily map well to COBOL error codes. To solve this problem, Acu4GL for ODBC allows you to create an error map file to map native database errors to COBOL errors. Create the file using the guidelines described on the following page, and then use the configuration file variable, A-ODBC-ERROR-MAP-FILE, to indicate the name and location of the file you created.
Example
If the file used for mapping is called MAP and this file is located in the directory C:\ODBC, you would specify:
A-ODBC-ERROR-MAP-FILE c:\ODBC\MAP
in the runtime configuration file. There is no default value for this variable.
Guidelines for creating a map file
Although you can check your data source documentation for error code information, the easiest way to determine what error codes need to be mapped to more appropriate COBOL codes is through trial and error. As users use Acu4GL for ODBC, they may report receiving error messages that don't make sense based on their situation. Research these errors and try to determine a more appropriate COBOL error response.
When you create your error map file, use the following guidelines:
Begin comment lines with #. Blank lines are also considered comments.
Break the rest of the file into sections, with each section header consisting of all the information enclosed in brackets from the data source error function.
For example, if the data source returns this error:
OdbcOneInfo: State: S1000, Native Error: -346 [Visigenic][ODBC Informix 5 Driver][Informix]Could not update a row in the table.
make your section header:
[Visigenic][ODBC Informix 5 Driver][Informix]
Include two fields in each line in the section: the internal error number, and an ACUCOBOL-GT mapping string.
Using the same example, if you wanted to map the Visigenic Informix driver error, "-346 Could not update a row in the table" to the COBOL error, "Not found", you would include this line in the section:
-346 E_NOT_FOUND
Other Visigenic Informix error maps would follow in the same section. If you use other drivers, you could use multiple sections.
The valid values for the second field are as follows:
E_SYS_ERR
E_PARAM_ERR
E_TOO_MANY_FILES
E_MODE_CLASH
E_REC_LOCKED
E_BROKEN
E_DUPLICATE
E_NOT_FOUND
E_UNDEF_RECORD
E_DISK_FULL
E_FILE_LOCKED
E_REC_CHANGED
E_MISMATCH
E_NO_MEMORY
E_MISSING_FILE
E_PERMISSION
E_NO_SUPPORT
E_NO_LOCKS
Through experience, Acucorp has discovered specific ways to better map errors for some drivers. For a list of these driver error mapping suggestions, look at the file odbcerrs on your installation disks.