How to determine if sql INSERTED or UPDATED? - sql

Question

Say I have a function like this:
Private Function addNicheMerge(ByVal tyNicheMergePOLE As typeNicheMergePOLE) As Integer Implements IGenie.addNicheMerge
Dim objParameterValues As New clsParameterValues
Dim objCon As DbConnection
Dim paramValues() As DbParameter
Dim iConnectionBLL As DataAccessLayer.Connection.iConnectionBLL
iConnectionBLL = New clsConnectionBLL()
Dim intCount As Integer
Try
tyAcornCollision = New typeAcornCollision
objParameterValues = New clsParameterValues
objCon = iConnectionBLL.getDatabaseTypeByDescription("GENIE2")
Using objCon
Dim strSQL As String
strSQL = "If NOT Exists (SELECT * FROM dbNicheMergeLog WHERE MasterID=#MasterID AND ChildID = #ChildID) "
strSQL = strSQL & "INSERT INTO dbNicheMergeLog (MasterID, ChildID, DateAdded, GenieUpdated, done, CheckedByUser, MergeTypeID, Usercode, LastUpdated) VALUES (#MasterID, #ChildID, getDate(), 0, 0, #CheckedByUser, #MergeTypeID, '', " & _ "GetDate()) Else Update dbNicheMergeLog SET LastUpdated = getdate() WHERE MasterID=#MasterID AND ChildID = #ChildID"
objParameterValues.AssignParameterValues("#MasterID", tyNicheMergePOLE.MasterID, 1)
objParameterValues.AssignParameterValues("#ChildID", tyNicheMergePOLE.ChildID, 1)
objParameterValues.AssignParameterValues("#MergeTypeID", tyNicheMergePOLE.MergeTypeID, 1)
objParameterValues.AssignParameterValues("#CheckedByUser", 0, 1)
paramValues = objParameterValues.getParameterValues
intCount = clsDatabaseHelper.ExecuteNonQuery(objCon, CommandType.Text, strSQL, paramValues)
Return intCount
End Using
Catch ex As Exception
Return -2
Finally
' If objCon.State = ConnectionState.Open Then
' objCon.Close()
' End If
objCon = Nothing
End Try
End Function
Is there a way to determine whether an insertion or update took place?

Answer 1

if you are using sql server, you could use an output clause to determine if an update happened
Update dbNicheMergeLog SET LastUpdated =
getdate() WHERE MasterID=#MasterID AND
ChildID = #ChildID
OUTPUT count(*)
Then in vb use
dim updateCount as int = Convert.ToInt32(clsDatabaseHelper.ExecuteScalar())

Answer 2

Try this SQL:
WITH new (
MasterID
,ChildID
,DateAdded
,GenieUpdated
,done
,CheckedByUser
,MergeTypeID
,Usercode
,LastUpdated
)
AS(
SELECT
#MasterID
,#ChildID
,getDate()
,0
,0
,#CheckedByUser
,#MergeTypeID
,''
,getdate()
)
MERGE INTO dbNicheMergeLog t
USING new
ON t.MasterID = new.MasterID
AND t.ChildID = new.ChildID
WHEN NOT MATCHED BY TARGET THEN
INSERT (
MasterID
,ChildID
,DateAdded
,GenieUpdated
,done
,CheckedByUser
,MergeTypeID
,Usercode
,LastUpdated
)
VALUES (
new.MasterID
,new.ChildID
,new.DateAdded
,new.GenieUpdated
,new.done
,new.CheckedByUser
,new.MergeTypeID
,new.Usercode
,new.LastUpdated
)
OUTPUT $action as Action
;

Answer 3

You can use
Output deleted.*
in your update query to get the results that were lost on update, something like this:
Create Table #abctest(
Id int identity,Name varchar(200))
Insert into #abctest(Name)
Values('abcd'),('bcde'),('cdef'),('defg'),('efgh'),('fghi')
Update #abctest Set Name='xyz' OUTPUT Deleted.* Where Id=2
The above query will give you an output
Id Name
2 bcde