__updatedAt未更新：Azure移动服务

Question

Azure Mobile Services is not updated the __updatedAt field when rows are updated. This is supposed to happen automatically. Is there anything that can be done to fix this? It was working automatically before, I don't know what could have possibly changed recently.

I'm working in Android.

Answer 1

When you create a table using the Mobile Service Azure Portal, it creates a trigger on the table that updates the __updatedAt column whenever a row is created or updated. The DDL for the trigger looks like this:

CREATE TRIGGER [(schema)].[TR_(table)_InsertUpdateDelete] ON [(schema)].[(table)]
WITH EXECUTE AS CALLER
AFTER INSERT, UPDATE, DELETE
AS
    BEGIN
        SET NOCOUNT ON;
        IF TRIGGER_NESTLEVEL() > 3 RETURN;

        UPDATE [(schema)].[(table)] SET [(schema)].[(table)].[__updatedAt] = CONVERT (DATETIMEOFFSET(3), SYSUTCDATETIME())
        FROM INSERTED
        WHERE INSERTED.id = [(schema)].[(table)].[id]
    END

The above is for Mobile Services. The newer Mobile Apps Easy Tables are slightly different: the column is named updatedAt without the __, and they use DATETIMEOFFSET(9) instead of (3).

Answer 2

Is the field not being updated in the database or in the client app? If it's the database, that means that someone has changed a SQL trigger, since that is what sets the field to change.

If it's the mobile client, note that __updatedAt is only sent to the client after the response has come from the server. So, if you're using offline sync, it will be once you do a PushAsync. If you're using the online tables, it will be in the modified object after the call to UpdateAsync.