Audit table update trigger does not work using a stored procedure

Question

I have table tblA

Which has a trigger defined on it, if any rows are updated it writes the changes to an audit table.

Now if on SQL Server I right click and edit a row directly, I see changes go to the audit table.

If I call a stored procedure to do an update, I do see tblA updated but the changed values do not go into the audit table. It seems like the trigger does not get fired at all.

What difference is there between directly editing a table or updating through a stored procedure in term of the trigger being fired.

---

Trigger 

USE [dbSuppHousing]
GO
/****** Object:  Trigger [dbo].[tblSurvey_trigger]    Script Date: 9/22/2015 2:32:51 PM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
/* =============================================
 
 Create date: 08/27/15
 Description:   Trigger to Add audit records to audtSurvey
                        
// =============================================*/
ALTER TRIGGER [dbo].[tblSurvey_trigger] on [dbo].[tblSurvey] 

FOR UPDATE,DELETE

AS

SET NOCOUNT ON

Declare   @FieldName varchar(100)
        , @Deleted varchar(4000)
        , @Inserted varchar(4000)
        , @SurveyID numeric
        , @LoginName varchar(100)

Declare  @currentDate datetime = null                                   
SET @currentDate = getdate()

Set @Deleted = ''
Set @Inserted = ''

Select * into #Deleted From Deleted
Select * into #Inserted From Inserted

Create Table #DT ([NameValue] varchar(1000))
Create Table #IT ([NameValue] varchar(1000))

Begin Transaction
    Declare  auSurveyCur cursor for Select Survey_ID from #Deleted Order By Survey_ID
    open auSurveyCur
    fetch next from auSurveyCur into @SurveyID
    while @@fetch_status = 0
        Begin
                Declare  auU cursor 
                for Select [name] from syscolumns where id = object_id('dbo.tblSurvey')
                open auU
                fetch next from auU into @FieldName
                while @@fetch_status = 0
                Begin
                    
                    Insert into #DT execute ('Select ' + @FieldName + ' From #Deleted Where Survey_ID = ' + @SurveyID)
                    Insert into #IT execute ('Select ' + @FieldName + ' From #Inserted Where Survey_ID = ' + @SurveyID)
                    
                            
                                Set @Deleted = (Select isnull(NameValue,'--') From #DT)
                                Set @Inserted = (Select isnull(NameValue,'--') From #IT)
                                If (@Deleted <> @Inserted)
                                Begin
                                    SELECT @LoginName=Login_Name
                                
                                    From Inserted Where Survey_ID=@SurveyID
                                    if @Deleted = '--' begin set @Deleted = null end 
                                    if @Inserted = '--' begin set @Inserted = null end 
                                    
                                    --@ForWhat=1 means info is for tbSurvey 
                                    --In future there may be more tables for auditing and we use same
                                    --Stored procedure to insert audit. Each table has its own audit table.

                                

                                    Execute dbo.InsertauInfo @Surv_ID=@SurveyID
                                                            , @auSurveyFieldName=@FieldName
                                                            , @auSurveyChangedFrom=@Deleted
                                                            , @auSurveyChangedTo=@Inserted
                                                            , @auSurveyUpdatedBy=@LoginName
                                                            , @auSurveyUpdateDate=@currentDate
                                                            , @ForWhat=1
                                End
                    Delete From #DT
                    Delete From #IT
                    fetch next from auU into @FieldName
                End
                close auU
                deallocate auU
                fetch next from auSurveyCur into @SurveyID
        END
    
    close auSurveyCur
    deallocate auSurveyCur
Commit  Transaction

---

Code for InsertauInfo

ALTER PROCEDURE [dbo].[InsertauInfo]
@Surv_ID bigint,
@auSurveyFieldName varchar(100),
@auSurveyChangedFrom varchar(max),
@auSurveyChangedTo varchar(max),
@auSurveyUpdatedBy varchar(100),
@auSurveyUpdateDate datetime,
@ForWhat int

AS

BEGIN   
    SET NOCOUNT ON; 
    IF (@ForWhat=1)
    BEGIN
        INSERT INTO auSurvey
                            ( Survey_ID
                            , auSurveyFieldName
                            , auSurveyChangedFrom
                            , auSurveyChangedTo
                            , auSurveyUpdateDate
                            , auSurveyUpdatedBy
                            )
        VALUES
                            ( @Surv_ID
                            , @auSurveyFieldName
                            , @auSurveyChangedFrom
                            , @auSurveyChangedTo
                            , @auSurveyUpdateDate
                            , @auSurveyUpdatedBy                            
                            )
    END

--ELSE IF (@ForWhat=2)
--      BEGIN
--              INSERT INTO ABC
                                
--      END 
END

Example of stored procedure which does not cause trigger to fire:

OK I'm going crazy but if I run this very simple stored procedure directly in DB, the trigger gets fired. But if I run from my C# web, the stored procedure will run since tblSurvey gets updated but trigger won't get fired.

ALTER PROCEDURE [dbo].[spUpdateSurveyDataTest]


AS
BEGIN

Update tblSurvey

Set 
[s1FirstName]='YES TRIGGER WORKS  for sureYES'
Where Survey_Id=327

  
END

Answer 1

The point of matter was as I mentioned in the question:

Trigger could not be run from App but I was able to fire it directly from a database update.

The problem was application was connecting to DB with its own generic User which did not have Execute permission for Trigger.

To make things more complicated there was no exception at application level.

The fix was to add

WITH EXECUTE AS OWNER 

To the trigger.