Specifying SQL Features Supported by a Database

When you import the schema or specify a database type in the General tab of the Database dialog box, the Feature table is automatically populated with default values appropriate for the database type. These are the SQL features that the Oracle BI Server uses with this data source.

You can tailor the default query features for a database. For example, if a data source supports left outer join queries but you want to prohibit the Oracle BI Server from sending such queries to a particular database, you can change this default setting in the Feature table.

CAUTION:  Be very careful when modifying the Feature table. If you enable SQL features that the database does not support, your query may return errors and unexpected results. If you disable supported SQL features, the server could issue less efficient SQL to the database.

To specify SQL features supported by a database

1. In the Physical layer of the Administration Tool, double-click the database.
2. In the Database dialog box, click the Features tab.
3. In the Features tab, use the information in Table 6 to help you specify properties for each SQL features.

Table 6. SQL Feature Tab Descriptions

Field or Button	Description
Ask DBMS	A button that is used only if you are installing and querying a database that has no Features table. It allows you to query this database for Feature table entries. For more information, refer to Changing Feature Table Entries Using Ask DBMS.
Default	A check box that identifies default SQL features. Default SQL features that are supported by the database type of the data source are automatically selected.
Find	A button that allows you to type a string to help you locate a feature in the list.
Find Again	A button that becomes available after you click Find. Allows you to perform multiple searches for the same string.
Revert to Defaults	A button that restores the default values.
Value	A check box that allows you to specify additional SQL features. Select to enable a query type or clear to disable a query type. It is strongly recommended that you do not disable the default SQL features.

Changing Feature Table Entries Using Ask DBMS

You should use the Ask DBMS button only if installing and querying a database that has no Features table.

NOTE:  The Ask DBMS button is not available if you are using an XML or a multidimensional data source.

The Ask DBMS button on the Features tab of the Database dialog box allows you to query a database for the SQL features it supports. You can change the entries that appear in the Feature table based on your query results.

CAUTION:  Be very careful when using Ask DBMS. The results of the features query are not always an accurate reflection of the SQL features actually supported by the data source. You should only use this functionality with the assistance of Oracle Technical Support.