This first long section describes in detail how the metadata describing the database and the required SDO model is supplied to the Relational DAS.When the constructor for the Relational DAS is invoked, it needs to be passed several pieces of information.
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The Relational DAS throws exceptions in the event that it finds errors in the metadata or errors when executing SQL statements against the database.
For brevity the examples below all omit the use of try/catch blocks around the calls to the Relational DAS.
The bulk of the information, passed as an associative array in the first argument to the constructor, tells the Relational DAS what it needs to know about the relational database.
It describes the names of the tables, columns, primary keys and foreign keys.