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Volumetrics in a Data Model

You can use volumetrics in a data model to calculate the size of tables, indexes, and physical storage objects in your database. When you calculate database size and growth, you can:

• Forecast hardware requirements.
• Evaluate the implications of database growth.
• Create what if scenarios based on server, physical object, column, and table settings.

You can select any table and calculate its approximate size according to the initial state or projected growth. After you calculate all table sizes in your database, you can calculate the approximate size of the entire database. When estimating the size of a database table, the data types that are native to the DBMS you are using are considered.

Using volumetrics, you can:

• Manipulate server-specific column values such as NULL and variable-width columns that influence table size calculations.
• Include index files in database calculations and select appropriate physical storage objects for each individual table in the database.
• Modify various parameters that affect database size calculations. For example, you can change the number of bytes per character, adjust the amount of space overhead per row, and include a log space factor to account for database log space.

You can also use volumetrics in a data model to calculate the size of entities in a logical or logical/physical model. When you calculate entity size in a logical model, it enables you to have volumetrics information in place when you derive a physical model from the logical model. In a logical/physical model, the information is persisted to the table properties on the physical side.

More information:

Calculate Table and Database Size

Define a Volumetrics Report

Set Volumetrics Database Parameters

Specify Volumetric Information for a Table

Specify Volumetric Information for an Entity