6-4 Metadata Repository Builders Guide for Oracle Business Intelligence Enterprise Edition
– Access the advanced SQL page of Answers to create requests. For more
information, see Oracle Fusion Middleware Users Guide for Oracle Business Intelligence Enterprise Edition.
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Set up groupuser-based permissions on Oracle BI Presentation Services to control access to editing preconfigured to allow access by Oracle BI Presentation Services
administrators and executing preconfigured to not allow access by anyone direct database requests. For more information, see Oracle Fusion Middleware
Security Guide for Oracle Business Intelligence Enterprise Edition.
Specifying SQL Features Supported by a Data Source
When you import metadata or specify a database type in the General tab of the Database dialog, the set of features for that database object 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.
When a feature is marked as supported checked in the Features tab of the Database dialog, the Oracle BI Server typically pushes the function or calculation down to the
data source for improved performance. When a function or feature is not supported in the data source, the calculation or processing is performed in the Oracle BI Server.
The supported features list in the Features tab uses the feature defaults defined in the DBFeatures.INI file, located in ORACLE_
INSTANCE\config\OracleBIServerComponent\coreapplication_obisn. Although you should not modify this file directly, it can be useful to look at this file to compare the
features supported by different data source types.
You can tailor the query features for a data source. For example, a new version of a data source may be released with updated feature support that is not reflected in the
Oracle BI Server defaults. In this case, you can update the settings in the Features tab to reflect the actual features supported by the new version of the data source. Or, if a
data source supports a particular feature such as left outer join queries but you want to prohibit the Oracle BI Server from sending such queries to a particular data source,
you can change this default setting in the Features tab. A third situation is when you have federated data sources that execute functions differently. To ensure query results
are consistent, you can disable the appropriate functions so that the calculations are performed in a consistent manner in the Oracle BI Server.
To specify SQL features supported by a data source: 1.
In the Administration Tool, in the Physical layer, double-click the database for which you want to specify SQL features.
2. In the Database dialog, click the Features tab.
3. In the Features tab, use the information in
Table 6–2 to help you specify properties
for each SQL feature.
Caution: Be very careful when modifying the set of supported
features in the Features tab. If you enable SQL features that the data source 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 data source.
In most cases, you should keep the default values. If you do change the defaults to mark a feature as supported in the Features tab, make
sure that the feature is actually supported by the data source.
Setting Up Database Objects and Connection Pools 6-5
About Connection Pools
The connection pool is an object in the Physical layer that describes access to the data source. It contains information about the connection between the Oracle BI Server and
that data source.
The Physical layer in the Administration Tool contains at least one connection pool for each database. When you create the Physical layer by importing a schema for a data
source, the connection pool is created automatically. You can configure multiple connection pools for a database. Connection pools allow multiple concurrent data
source requests queries to share a single database connection, reducing the overhead of connecting to a database.
Table 6–2 Options in the Features Tab of the Database Dialog
Option Description
Feature The name of the database feature, such as COUNT_DISTINCT_
SUPPORTED. Value
Shows the current value for the given feature. Selected indicates that the feature is supported in the data source, and that the
function or feature should be performed in the data source rather than in the Oracle BI Server.
Some features show a default value in the Value column rather than selectednot selected, such as 10 for MAX_ENTRIES_PER_
IN_LIST. It is strongly recommended that you keep the default selections
and default values. Default
Shows the default value for the given feature. The defaults listed in this column are specified in the file DBFeatures.INI.
Find Lets you type a string to help you locate a feature in the list.
Find Again This option becomes available after you click Find. It lets you
perform multiple searches for the same string. Query DBMS
This button is only used if you are installing and querying a data source that has no set of feature defaults in the Oracle BI
Server. It lets you query this type of data source for Feature table entries so that you can find out which SQL features it
supports. You can then change the entries that appear in the Features tab based on your query results.
This button is not available if you are using an XML or a multidimensional data source.
Caution: Be very careful when using the Query DBMS feature.
The results of the features query are not always an accurate reflection of the SQL features actually supported by the data
source. When using this feature, you should verify that the list of supported features in the Features tab matches the actual
features supported by your data source. Refer to the documentation for your data source for details.
Reset to defaults This button restores the default values for this data source type
from the file DBFeatures.INI.
Note: Do not change the OPTIMIZE_MDX_FILTER_
QUALIFICATION feature. This parameter is reserved for a future release.
6-6 Metadata Repository Builders Guide for Oracle Business Intelligence Enterprise Edition
For each connection pool, you must specify the maximum number of concurrent connections allowed. After this limit is reached, the connection request waits until a
connection becomes available.
Increasing the allowed number of concurrent connections can potentially increase the load on the underlying database accessed by the connection pool. Test and consult
with your DBA to make sure the data source can handle the number of connections specified in the connection pool. Also, if the data sources have a charge back system
based on the number of connections, you might want to limit the number of concurrent connections to keep the charge-back costs down.
In addition to the potential load and costs associated with the database resources, the Oracle BI Server allocates shared memory for each connection upon server startup.
This raises the number of connections and increases Oracle BI Server memory usage.
About Connection Pools for Initialization Blocks
It is recommended that you create a dedicated connection pool for initialization blocks. This connection pool should not be used for queries.
Additionally, it is recommended that you isolate the connections pools for different types of initialization blocks. This also makes sure that authentication and
login-specific initialization blocks do not slow down the login process. The following types should have separate connection pools:
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All authentication and login-specific initialization blocks such as language, externalized strings, and group assignments.
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All initialization blocks that set session variables.
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All initialization blocks that set repository variables. These initialization blocks should always be run using credentials with administrator privileges.
Be aware of the number of these initialization blocks, their scheduled refresh rate, and when they are scheduled to run. Typically, it would take an extreme case for
this scenario to affect resources. For example, refresh rates set in minutes, greater than 15 initialization blocks that refresh concurrently, and a situation in which
either of these scenarios could occur during prime user access time frames.
Initialization blocks should be designed so that the maximum number of Oracle BI Server variables may be assigned by each block. For example, if you have five
variables, it is more efficient and less resource intensive to construct a single initialization block containing all five variables. When using one initialization block,
the values are resolved with one call to the back end tables using the initialization string. Constructing five initialization blocks, one for each variable, would result in
five calls to the back end tables for assignment.
See Working with Initialization Blocks
for more information about these objects.
Creating or Changing Connection Pools
Typically, database objects and connection pools are created automatically when you import physical schemas, for both relational and multidimensional data sources. If you
did not import physical schemas, you must create a database object before you create a
Note: It is recommended that you create a dedicated connection pool
for initialization blocks. See About Connection Pools for Initialization
Blocks for more information.
Setting Up Database Objects and Connection Pools 6-7
connection pool. You create or change a connection pool in the Physical layer of the Administration Tool.
If you have already defined an existing database and connection pool, you can right-click the connection pool in the Physical layer and select Import Metadata to
import metadata for this data source. The Import Metadata Wizard appears with the information on the Select Data Source screen pre-filled. See
Chapter 4, Importing Metadata and Working with Data Sources
for information about the Import Wizard. To automate connection pool changes for use in a process such as production
migration, consider using the Oracle BI Server XML API. See About the Oracle BI Server XML API in Oracle Fusion Middleware Integrators Guide for Oracle Business
Intelligence Enterprise Edition for more information.
To create or change a connection pool: 1.
In the Physical layer of the Administration Tool, right-click a database and select New Object
, then select Connection Pool. Or, double-click an existing connection
pool.
2. Specify or adjust the properties as needed, then click OK.
