How to: Add or Delete Conditions

[This page is specific to the latest version of the Entity Framework. The latest version is available as the 'Entity Framework' NuGet package. For more information, see Entity Framework Releases and Versioning.]

Conditions allow the mapping system to map a particular type in the hierarchy to or from rows in a table, based on the values of the selected condition columns. Entity types can define a set of conditions for each table to which they are mapped.

noteNote:
If an entity property maps to a particular column, that column cannot be used to create a condition. To delete the mapping of a property to a column, select the property in the Value/Property column of the Mapping Details window and select <Delete> .

The following table describes the fields in the Mapping Details window that are used to add a condition.

 

Name Description

Column

Contains an alphabetized list of all available columns. Columns that are already mapped in the entity are not displayed.

Operator

A drop-down list that provides two possible operators, = and Is .

Value/Property

If the Is operator is selected in the Operator field, the Value/Property field is a drop-down list with the values Null and Not Null .

If the column is a Boolean type and the = operator is selected in the Operator field, the Value/Property field is a drop-down list with the values True and False .

If the column is a String or Integer type and the = operator is selected in the Operator field, the Value/Property field is an editable text box.

To add a condition

  1. Expand the node of the table to which you want to add a condition.

  2. Click Add a Condition .

    The field becomes a drop-down list that displays the available columns in the table.

  3. Select a column from the list.

    The Column field now displays When <column_name> .

  4. Select an operator from the Operato r field.

  5. Type or select the condition value in the Value/Property field.

To delete a condition

  1. Click the Column field of the condition you want to remove.

    The field becomes a drop-down list.

  2. Select <Delete> .




Build Date:

2013-06-19
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