Configure additional Business Logic Tier (BLT) components

Note: For information on overriding default configuration settings, refer to Modifying Configuration Settings.

To mark a AVEVA Enterprise SCADA Business Logic Tier (BLT) component as available for execution via the Microsoft SQL Engine, it is necessary to configure some basic information about the BLT in the Microsoft SQL Engine configuration settings file.

Each BLT must be named, associated with a AVEVA Enterprise SCADA service, and identified as belonging to a particular datastore. Here is the configuration for the RealTime BLT components, as defined in the %DNAInstallRoot%\RealTime\config\Settings\SQLEngine_RealTime.json file:

{

"SQLEngine": {

"BLT": {

"RealTime": {

"NoResultSets": "\n\t\t\tRTDB.dbo.AddSYSalarm;\n\t\t\tRTDB.dbo.SpoolControl;\n\t\t\tRTDB.dbo.SpoolMsg\n\t\t",

"WithResultSets": "\n\t\t\tRTDB.dbo.Trend;\n\t\t\tRTDB.dbo.Trendview\n\t\t"

}

}

}

}

The hive must specify the AVEVA Enterprise SCADA service which must be running before the BLT is actually available: in the example above, it is the RealTime service.

The value definitions are divided into two categories based on what the BLTs return. Either the BLT returns one or more sets of tabular data and is categorized as WithResultSets, or it returns no tabular results, NoResultSets. No special configuration is required to identify input or output parameters. This information will be obtained at run-time from the BLT service.

The naming convention for a fully-qualified BLT is <database>.<owner>.<name>, thus the BLT components configured above are associated with the RTDB datastore. The string dbo stands for database owner and is not actually required (it’s just a placeholder). If the database or owner is not specified, the entry will default to SCHEMA and dbo, respectively. Multiple entries should be separated by a semi-colon. All whitespace between entries is ignored.

Note: The stored procedure names are case-sensitive when being executed, however the name in the configuration file is not case-sensitive. If the case of the name in the configuration file is not correct, it will be fixed automatically when the Microsoft SQL Engine applies the configuration at run-time. To expose additional RealTime BLT components to the Microsoft SQL Engine, edit the file and add the BLT name under the correct category.

To expose BLT components for other AVEVA Enterprise SCADA Services, the preferred method is to create a new Microsoft SQL Engine configuration settings file using a similar naming convention, and ensure that it is deployed to the servers where the Microsoft SQL Engine runs. You must restart the Microsoft SQL Engine for the modified configuration to take effect, as it is only read on start-up.