SubscriptionClass Element (ADF)

Contains the definition of one subscription class.

Syntax

<SubscriptionClasses>
    <SubscriptionClass>

Element Characteristics

Element Relationships

Remarks

If you delete a SubscriptionClass element, updating the application removes the subscription class and renames the existing subscription tables by appending Old to the table name. Existing subscription table indexes are left unchanged.

If you want to transfer data between the old and new subscription tables, it must be done manually. For more information, see Updating an Application.

Example

The following example shows a SubscriptionClass element that defines a subscription class for stock notifications. The subscription class does the following:

• Defines the subscriptions table, places the table in the Secondary filegroup, and defines an index for the table on the SubscriberID column, which Notification Services automatically includes in the subscription class schema.
• Creates an event rule for the subscription class that generates event-triggered notifications and updates the subscription chronicle.
• Creates a scheduled rule for the subscription class that generates scheduled subscriptions and updates the subscription chronicle.
• Creates the subscription chronicle.

<SubscriptionClass>
    <SubscriptionClassName>StockSubscriptions</SubscriptionClassName>
    <Schema>
        <Field>
            <FieldName>DeviceName</FieldName>
            <FieldType>nvarchar(255)</FieldType>
            <FieldTypeMods>NOT NULL</FieldTypeMods>
        </Field>
        <Field>
            <FieldName>SubscriberLocale</FieldName>
            <FieldType>nvarchar(10)</FieldType>
            <FieldTypeMods>NOT NULL</FieldTypeMods>
        </Field>
        <Field>
            <FieldName>StockSymbol</FieldName>
            <FieldType>char(10)</FieldType>
            <FieldTypeMods>NOT NULL</FieldTypeMods>
        </Field>
        <Field>
            <FieldName>StockTriggerPrice</FieldName>
            <FieldType>money</FieldType>
            <FieldTypeMods>NOT NULL DEFAULT 10</FieldTypeMods>
        </Field>
    </Schema>
    <FileGroup>Secondary</FileGroup>
    <IndexSqlSchema>
        <SqlStatement>
        CREATE INDEX StockSubIndex 
        ON StockSubscriptions (SubscriberId);
        </SqlStatement>
    </IndexSqlSchema>
    <EventRules>
        <EventRule>
            <RuleName>StockSubscriptionNotifyRule</RuleName>
            <Action>
            -- Generate event-triggered notifications
            INSERT INTO StockNotifications 
            ( SubscriberId, DeviceName, SubscriberLocale,
            StockSymbol, StockPrice )
            SELECT S.SubscriberId, S.DeviceName,
                S.SubscriberLocale, E.StockSymbol, E.StockPrice
            FROM StockSubscriptions S JOIN StockEvents E
            ON S.StockSymbol = E.StockSymbol
            JOIN StockEventChron C
            ON S.StockSymbol = C.StockSymbol
            WHERE S.StockTriggerPrice &lt;= E.StockPrice
            AND S.StockTriggerPrice &gt; C.StockHighPrice;
            -- Maintain subscription chronicle
            INSERT StockSubscriptionChron
            (SubscriberId, StockSymbol, StockPrice)
            SELECT S.SubscriberId, S.StockSymbol, E.StockPrice
            FROM StockSubscriptions S JOIN StockEvents E
            ON S.StockSymbol = E.StockSymbol;
            </Action>
            <ActionTimeout>P0DT00H01M00S</ActionTimeout>
            <EventClassName>StockEvents</EventClassName>
        </EventRule>
    </EventRules>
    <ScheduledRules>
        <ScheduledRule>
            <RuleName>StockSubScheduledRule</RuleName>
            <Action>
            -- Generate scheduled notifications
            INSERT INTO ScheduledNotifications
            ( SubscriberId, DeviceName, SubscriberLocale,
            StockSymbol, StockPrice )
            SELECT S.SubscriberId, S.DeviceName, 
                S.SubscriberLocale, C.StockSymbol, C.StockPrice
            FROM StockSubscriptions S JOIN StockEventChron C
            ON S.StockSymbol = C.StockSymbol 
            WHERE S.StockTriggerPrice &lt;= C.StockHighPrice 
            GROUP BY S.StockSymbol, C.StockHighPrice;
            -- Maintain subscription chronicle
            INSERT StockSubscriptionChron
            (SubscriberId, StockSymbol, StockPrice)
            SELECT S.SubscriberId, S.StockSymbol, C.StockHighPrice
            FROM StockSubscriptions S JOIN StockEventChron C
            ON S.StockSymbol = C.StockSymbol;
            </Action>
            <ActionTimeout>P0DT00H00M45S</ActionTimeout>
        </ScheduledRule>
    </ScheduledRules>
    <Chronicles>
        <Chronicle>
            <ChronicleName>StockSubscriptionChron</ChronicleName>
            <SqlSchema>
                <SqlStatement>
                IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES 
                WHERE TABLE_NAME = &apos;StockSubscriptionChron&apos;)
                DROP TABLE StockSubscriptionChron;
                </SqlStatement>
                <SqlStatement>
                CREATE TABLE StockSubscriptionChron
                (
                SubscriberId bigint,
                StockSymbol char(10),
                StockPrice money
                PRIMARY KEY (SubscriberId)
                );
                </SqlStatement>
            </SqlSchema>
        </Chronicle>
    </Chronicles>
</SubscriptionClass>

See Also

Reference

Application Definition File Reference

Other Resources

Defining the Core Subscription Class
Updating Instances and Applications

Help and Information

Getting SQL Server 2005 Assistance