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theCommandBroker.CurrSQL. The second argument, which is optional, represents an Ado connection. The remaining arguments are optional flags that you can use for additional purposes. |
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Finally, the object theDatabaseForm invokes its own displayCurrentRecord method to display the desired record that you make current. By default, for any opened set of records, the first record is made the current record. Then, using its private theForm object reference to, in this case, the frmPublishers form, theDatabaseForm invokes the Show method of the actual form reference. Because IDBSubsystem is a common facade for the three data access mechanisms, the same object interactions just described can be easily used with Dao and Rdo by replacing the eDataAccess.Ado parameters with either eDataAccess.Dao or eDataAccess.Rdo, respectively. When implementing IDBSubsystem within IPersistence (when necessary), simply declare the former within the General Declarations section of the latter as follows: |
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Public theDBSubsystem As IDBSubsystem |
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and then access as follows (assuming an object variable, thePersistence): |
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thePersistence.theDBSubsystem.DBConnection.openConnection _ sConnStr |
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The Database Access Class Hierarchy Model |
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Figure 19.3 shows the classes that make up the Database Access Subsystem. |
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Figure 19.3.
The classes in the Database Access Subsystem. |
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