Eagle maintains history tables and composite tables for entity and security data. Using Data Mart, you can select history data for entities and securities to use in reports. The history tables contain values tagged by Effective Date and Source to produce a complete history of past data loads. The composite tables contain current best values and are built from data loads and data history based on best data and composite rules.

The system loads entity data one record at a time. Entity data does not change frequently and no sources are defined. When an entity field changes, history gets a new record of all values. Security data is loaded one field at a time. As an example, this makes it possible to update just the coupon rate of a bond in a particular load of that bond's data. This is necessary because security data can come from a wide variety of sources.

Using Entity History

The Use Entity History check box on the Data Mart Configuration dialog box determines whether to extract data from the entity history tables or composite tables. The system bases this on the as of date of the model submission.
There is no option on the Data Mart Configuration dialog box to extract data from the security history tables. In the Source Rule used to populate Data Mart, you must include one or more sources in the folders of the security data for which you want to use history, such as Analytics, Price, Ratings, and Securities.

History data is more time consuming to use than composite data. In Data Mart, history is built in because rows are written every day to the Fund Summary (entity data) table and Security Details (security data) tables. For daily builds of the Data Mart, history tables may not be worth the extra time required. But, if you are building data for past dates, such as back-filling history for a new field, you may want to use history to properly reflect an as of view. You may also want to select security sources in a Snapshot's Source Rule to reflect a different source preference than the one in the composite security data. You can specify this in your default Source Rule by omitting security sources.

The Use Most Recent Entity Data and Use Most Recent Security Data check boxes on the Data Mart Configuration dialog box determine how your use of history data handles the possible presence of null values.

Using the Most Recent Security Data Example

The following table displays security history data for two fields in the Security Details model. The Source Rule includes the sources IDSI and Bloomberg.

The following table illustrates how the Use Most Recent Security Data option works using the security history data in the previous table.

*Field level settings do not have to be the same for all fields in the table. It is shown this way for simplicity.

Build Security Information

You can build security data for any of three definitions of the securities in your security master table. The Security Build Information option is available on the Data Mart Configuration dialog box.

To build the security information:

1. In Reporting Center, from the left navigation, select Reporting Tools > Datamart > Manage Marts > Data Mart.
   You see the Data Mart workspace.
2. Select the data mart you want to configure.
3. Click Administration link and then click Configure.
   You see the Data Mart Configuration dialog box.
4. Under Security Build Information section, select a security type to build. Options include:
   - Click Build All Securities to build all securities in your Security Master.
   - Click Held securities, and add criteria to include more to build only held securities. Do not click Define Criteria to include unheld securities.
   - Click Held securities..., then click Define Criteria to build held securities plus unheld securities that pass certain criteria you set up.
     You see the Define Data Mart Security Build Criteria dialog box.
    
5. Create a filter to select securities from the Security Master file for use in populating the Security Details table.
6. Click OK.
   Data Mart applies the filter the next time you build Security Details.
   Note: If you change the criteria and re-populate the Security Details table with an Effective Date that has been populated before, the previously populated securities are not deleted from the table. If you change the criteria and re-populate the Security Details table with an Effective Date that has never been populated, only securities represented in other Details tables or passing your filter are displayed.