FieldTypeMods Element for EventClass/Schema/Field (ADF)
Specifies optional Microsoft SQL Server field attributes for an event field, such as null and default values.
Sintassi
<EventClasses>
<EventClass>
...
<Schema>
<Field>
...
<FieldTypeMods>
Element Characteristics
Characteristic | Description |
---|---|
Data type |
string, between 1 and 255 characters in length. |
Default value |
None. |
Occurrence |
Optional once per Field element. |
Updates |
Can be added, deleted, and modified when updating the application. |
Element Relationships
Relationship | Elements |
---|---|
Parent element |
|
Child elements |
None. |
Osservazioni
The possible values for FieldTypeMods come from the table column modifiers, such as NOT NULL or DEFAULTconstant_expression. The value must conform to the Transact-SQL syntax conventions.
[!NOTA] You cannot specify an event data field as an Identity column in SQL Server. Notification Services already uses the Identity property to specify a system-generated EventId field.
For more information about possible values, see CREATE TABLE (Transact-SQL).
Importante: |
---|
If you update a FieldTypeMods element, updating the application deletes and re-creates the event class to which it corresponds. This includes dropping and re-creating the SQL Server tables and indexes used by this event class. Any data existing in the original event class tables is permanently deleted. |
Esempio
The following example shows how to specify that the event class field does not accept a null value.
<FieldTypeMods>NOT NULL</FieldTypeMods>
Vedere anche
Riferimento
Application Definition File Reference
Altre risorse
Definizione delle proprietà di una classe di evento principale
Aggiornamento di istanze e applicazioni