Originally posted by: SystemAdmin

When I wrote .dat file connecting to oracle, the data element "nperiod" in .dat file type is int,and in the oracle its type is number, and I run the model, the mistake happening "Data element "nperiod" of type int not supported for databases", I don't why ? And how to solve it?

Thank you!
#DecisionOptimization
#OPLusingCPLEXOptimizer

Originally posted by: SystemAdmin

Hi,

When reading data from a database, the OPL data you're initializing has to be an array or a set.
In the documentation for DBRead(), it says "The DBRead instruction is used to read data from a database and insert the data elements into an OPL array or an OPL set."

If you're interested in getting an integer (not a set nor an array), the workaround is to first read a set and then get that element with something like:

int period = first(setReadFromDB);

Hope this helps
#DecisionOptimization
#OPLusingCPLEXOptimizer

Originally posted by: SystemAdmin

Thanks！
It was the problem! And with your help,I've solved it!
Yes,the data type from or to the database must be array or set, if not,the error message will be shown up.

Thanks again!
#DecisionOptimization
#OPLusingCPLEXOptimizer