Creating a New Project DATABASE CONFIGURATION The Database Configuration dialog allows you to configure the necessary settings to link IWS to an external database file. Database Configuration dialog • Database combo-box: Allows you to select either Primary or Secondary. With Primary, all settings displayed in the Database Configuration window apply to the Primary Database interface. Otherwise, they apply to the Secondary Database interface. You can configure the Secondary database in the following modes: • Disabled : In this mode, IWS saves data in the Primary Database only. If the Primary Database is unavailable for any reason, the data is not saved anywhere else.
This option may cause loss of data if the Primary Database is not available. • Redundant : In this mode, IWS saves data in both Primary and Secondary Databases. If one of these databases is unavailable, IWS keeps saving data only in the database that is available. When the database that was unavailable becomes available again, IWS synchronizes both databases automatically. • Store and Forward : In this mode, IWS saves data in the Primary Database only. If the Primary Database becomes unavailable, IWS saves the data in the Secondary Database. When the Primary Database becomes available again, IWS moves the data from the Secondary Database into the Primary Database. Note:
The Primary and Secondary can be different types of databases. However, they must have the same fields. Using the Secondary Database, you can increase the reliability of the system and use the Secondary Database as a backup when the Primary Database is not available. This architecture is particularly useful when the Primary Database is located in the remote station. In this case, you can configure a Secondary Database in the local station to save data temporarily if the Primary Database is not available (during a network failure, for instance). • Use project default checkbox:
When this option is checked, IWS uses the settings configured in the Default Database for the task that is being configured (Connection string, User name, Password, Retry Interval and Advanced Settings). When this option is not checked, you can configure these settings individually to the current task. • Connection string field: This field defines the database where IWS will write and read values as well as the main parameters used when connecting to the database. Instead of writing the Connection string InduSoft Web Studio Page 79