Figure 4.38: The Database Options Dialog Box
You can change the various preferences for MPL by choosing Database from the Options menu. This will display the Database Options dialog box shown below.
Figure 4.38: The Database Options Dialog Box
| Option Name | MPL Name | Solver Param | ParamNr | Type | Default | Min | Max |
|---|---|---|---|---|---|---|---|
| Database connection Default | DatabaseType | list | 0 | 0 | 40 | ||
| Database Directory | DatabaseDirectory | string | |||||
| User | DatabaseUsername | string | |||||
| Password | DatabasePassword | string | |||||
| Do not export | DoNotExport | Flag | 0 | 0 | 1 | ||
| Export zero values | ExportZeros | Flag | 0 | 0 | 1 | ||
| Export MPL symbols | ExportGenerate | Flag | 1 | 0 | 1 | ||
| Use Transactions | UseTransact | Flag | 1 | 0 | 1 | ||
| Interval | TransactInterval | Integer | 10000 | 10000 | MAXINT |
Chooses which of the supported databases is the default for the MPL Database Connection. MPL supports both specific databases, such as FoxPro and Paradox, as well as the databases that are supported by the ODBC standard such as Access.
Depending on which database is selected, this entry will specify the database directory or the data source that MPL will use as default when importing data. For Xbase type databases, such as FoxPro and Paradox, this will typically be the directory where the database files are stored. For ODBC type databases this either be a database file, such as (filename.mdb) for MS Access and (filename.xls) for Excel, or a defined ODBC datasource that can be specified in the ODBC control panel.
Databases often require a username to log in, this option can be used to specify this.
Along with a username a password is often require to allow access to the data. This option allows one to put in the passowrd.
Do not export solution values to database even if there are export statements in the model.
When exporting using either CREATE or REFILL, this option specifies whether records with zero activity values should also be exported. The default value is Off since in most cases only the nonzero records are needed.
When exporting MPL symbols such as; indexes and datavectors, they are generally only exported when model is solved and not when an input file is generated. This options directs MPL to export symbols when input files are generated, since this might be useful for debugging purposes. The default value is Off.
Directs MPL to use transactions when exporting to a database. Using transactions can greatly improve speed especially when working with remote databases. Please note, that not all databases support transactions. The default value is On.
Specifies what the interval should be between when the transactions are performed.