Physical Modeling › Columns › Define Basic Table Column Properties

Previous Topic: Add a Column to a Table Using the Table Column Editor

Next Topic: Defining Table Column Properties for Target Databases

Define Basic Table Column Properties

In a physical model based on either the MySQL, ODBC, or Sybase target server, the <database> tab in the Table Column Editor contains options for defining common table column properties such as physical data type and null option.

To define table column properties

  1. Right-click a column in the Model Explorer and click Properties.

    The <database> Table Column Editor opens.

  2. Select the table from the Table drop-down that contains the column that you want to define.
  3. Select the column in the Navigation Grid that you want to define.

    Note: Click New New icon in property editors to create a new object on the toolbar to create a new column. Use the Enter filter text box to filter a very large list of columns to quickly locate the one that you want to define.

  4. Click the <database> tab and work with the following options:
    Physical Data type

    Lets you select a data type from the drop-down list to apply to the selected column. If the selected data type requires a value for precision, scale, or both, enter the value inside the data type parentheses. For example, you can select the DECIMAL() data type and specify a precision of 2 and a scale of 10 inside the parentheses to assign the data type DECIMAL(2,10) to the selected column.

    Null Option

    Lets you specify a null option for the selected column.

    Average Width

    Lets you enter an estimated average width for the column if variable width is allowed based on the data type you assigned. If it is not allowed, an error is displayed in the Details section at the bottom of the editor. You can later use the Volumetrics dialog to calculate table and database size estimates based on these and other values.

    Percent Null

    Lets you enter the estimated percentage of nulls used for that column if the option is available. For example, you can estimate a variable width ADDRESS 2 column assigned a width of 50 characters, to be NULL about 30 percent of the time. Use whole numbers. You can later use the Volumetrics dialog to calculate table and database size estimates based on these and other values.

  5. Click Close.

    Table column properties are defined and the <database> Table Column Editor closes.

More information:

Defining Table Column Properties for Target Databases