Siebel Data Warehouse Installation and Administration Guide > DAC Functional Reference > About the DAC Design View >

About the DAC Indices Tab

The Indices tab displays a list of all the indices of all the data warehouse tables. It is recommended that you do not register any indices for source tables. During the ETL process, when a table is going to be truncated, all the indices as defined in the repository will be dropped before the data is loaded and will be created after the data is loaded automatically. While this improves the ETL performance, the preconfigured workflows have the bulk load option turned on. The bulk load will fail if there are indices on the table. Therefore, it is important to keep the index definitions in sync with the database. For example, if you create an index on the database, and it is not registered in the repository, the index will not be dropped and the load will fail.

Table 24 provides a description of the index properties displayed in the list.

Table 24.  DAC Indices Tab List Columns
Column
Description
Name
Unique name with which the index is created.
Table Name
Table for which an index is created.
Index Type
Type of index: ETL or Query. An ETL index is typically used during the ETL process. A Query index is an index is used only during the reporting process. It is recommended that you have a clear understanding of when and where the index will be used at the time of registering the index.
# Unique Columns
For unique indices, the number of columns that will be unique.
Is Unique
Indicates whether the index is unique.
Is Clustered
Indicates whether the index is clustered. There can be only one clustered index per table.
Is Bitmap
Indicates whether the index is of the bitmap type.
Allow Reverse Scan
Applicable only for DB2-UDB databases. The index will be created with the Allow Reverse Scan option.
Table Space Name
Applicable only for Oracle databases. If a table space is mentioned, an index is created in that particular table space. If all indices go to a table space different from the data area, you can define it in the ETL Preferences (Tools > ETL Management> Preferences).
Inactive
Indicates whether an index is active or inactive. Inactive indices do not participate in the ETL process.

Table 25 shows which index properties are available for the different database types that are supported.

Table 25.  Index Properties and Database Types Matrix
Column/
Database
Is Unique
Is Clustered
Is Bitmap
Allow Reverse Scan
# Unique Columns
Oracle
X
 
X
 
 
DB2
X
X
 
X
X
DB2-390
X
 
 
 
 
MSSQL
X
X
 
 
 

Table 26 provides a description of the tabs in the bottom pane.

Table 26.  Indices Subtabs
Tab
Description
Edit
Allows you to edit the table selected in the top pane.
Description
Displays a description of the table selected in the top pane.
Columns
Displays the list of columns the index is made of.
The list of columns contains the following column headings:
  • Name. Name of the column.
  • Position. Position of the column in the index.
  • Sort Order. Indicates whether the sort order is ascending or descending.
  • Inactive. Indicates whether the column is active or inactive.
Databases
Indicates whether an index is applicable only to a certain type of database. If no database is indicated, the index will always be created.

Actions Available

The following actions are available in the top pane toolbar and in the right-click menu when the Indices tab is active.

Copy Record

This command creates a copy of the selected index.


 Siebel Data Warehouse Installation and Administration Guide
 Published: 11 March 2004