Data Base trigger after table create on mssql - sql

Question

I got a data base trigger after table create.
CREATE TRIGGER tr_Timestamps_TableTriggersCreation
ON DATABASE
AFTER CREATE_TABLE
AS
BEGIN
SET NOCOUNT ON
DECLARE #tableName SYSNAME
DECLARE #schemaName SYSNAME = NULL
DECLARE #totalRows INT = 0;
SELECT #tableName = EVENTDATA().value('(/EVENT_INSTANCE/ObjectName)[1]','SYSNAME')
SELECT TOP 1 #schemaName = s.name
FROM sys.tables t
JOIN sys.columns c ON c.object_id = t.object_id
JOIN sys.schemas s ON s.schema_id = t.schema_id
WHERE t.name = #tableName
AND c.name = 'ID'
IF (#schemaName != '')
BEGIN
EXEC u_general.sp_Timestamps_TriggerForTableCreation #tableName, #schemaName, 'I'
EXEC u_general.sp_Timestamps_TriggerForTableCreation #tableName, #schemaName, 'U'
END
The idea behind it is to create 2 trigger for each table which is being created on that database.
My problem is as follow,
When someone uses the MSSQL 'editor' and uses the 'Design' option instead of writing a script for making changes such as marking a column for 'Allow Null or not', change the data type etc...
My Data base trigger counts it as a new table creation and launches the procedure which create the triggers for that table.
The end result is that it tries to create those triggers again and i get an error message that those triggers already exist.
ALTER PROCEDURE [u_general].[sp_Timestamps_TriggerForTableCreation] ( #tableName sysname, #schemaName sysname, #actionType char(1))
AS
DECLARE #TrigerName NVARCHAR(50)
DECLARE #AfterActionName NVARCHAR(50)
IF #actionType = 'I'
BEGIN
SET #TrigerName = 'tr_Timestamps_CaptureAfterInsert_' + #tableName
SET #AfterActionName = 'INSERT'
END
ELSE -- 'U'
BEGIN
SET #TrigerName = 'tr_Timestamps_CaptureAfterUpdate_' + #tableName
SET #AfterActionName = 'UPDATE'
END
DECLARE #SQLCommand nvarchar(max)=
'CREATE TRIGGER ' + #TrigerName +'
ON ' + #schemaName + '.' + #tableName +
' AFTER '+ #AfterActionName +'
AS
DECLARE #auditBody XML
DECLARE #RowID int
SELECT #RowID = INSERTED.ID FROM INSERTED
SELECT #auditBody =
''<Timestamps_Request>
<DataBaseName>'' + DB_NAME() + ''</DataBaseName>
<SchemaName>'' + ''' + #schemaName + ''' + ''</SchemaName>
<TableName>'' + ''' + #tableName + '''+ ''</TableName>
<RowID>'' + CAST(#RowID AS NVARCHAR(30)) + ''</RowID>
<Action>'' + '''+#actionType+''' + ''</Action>
</Timestamps_Request>''
EXEC u_general.sp_Timestamps_SendBrokerMessage #FromService = ''Timestamps_RequestService'',
#ToService = ''Timestamps_ProcessingService'',
#Contract = ''Timestamps_Contract'',
#MessageType = ''Timestamps_Request'',
#MessageBody = #auditBody ';
EXEC sp_executeSQL #SQLCommand
My question is,
What can i do to make sure that it wont happen every time someone decides to use the designer for 'altering' a table?
P.S. From my understanding it has something to do with the SSMS (causes drop and create? ) and the way it works, and this is why i dont have this issue while using a script to modify the table instead of the MSSQL designer.

Answer 1

Quick Note before direct answer.
Use DDL Events with CREATE_TABLE and Confirm you Don't using Alter_TABLE within your Trigger definitions, because CREATE_TABLE and Alter_TABLE is totally separated events.
Follow the next Demo for more Details.
Demo:-
Create table table1 (col1 int, col2 nvarchar(10) not null )
go
Create TRIGGER NoCreateNewTables ON DATABASE
FOR CREATE_TABLE
AS
Print 'Prevent Table Creation'
BEGIN
ROLLBACK;
END
GO
Lets Alter Table1 Via next:
ALTER TABLE table1 ALTER COLUMN col2 nvarchar(10) NULL
Result:-
Lets Create new table Table2 Via next:
Create table table2 (col1 int, col2 nvarchar(10) not null )
Result:-
What about SSMS
The direct answer starts here
SQL Server drops and recreates the tables while using SSMS designer in some cases:
Common cases:-
Add a new column.
Change the Allow Nulls setting for a column.
Change the column order in the table.
Change the column data type.
After some investigation , I noticed the Object_Name that altered via SSMS designer Starts with Tmp_.
so according to this info we can prevent alter table via SSMS designer by Create Trigger for Preventing altering table from SSMS while table recreated.
Demo:-
/* Create Trigger for Preventing altering table Via SSMS while table recreated */
Create TRIGGER TrgPreventAlterTableIfTableRecreatedViaSSMSDesign ON DATABASE
FOR CREATE_TABLE
AS
BEGIN
DECLARE
#eventInfo XML,
#ObjectName varchar(100)
SET
#eventInfo = EVENTDATA()
select #ObjectName = CONVERT(SYSNAME, #eventInfo.query('data(/EVENT_INSTANCE/ObjectName)'))
if (Left(#ObjectName,3) = 'Tmp')
begin
exec sp_addmessage 50001, 16,
N'Cannot modify Table Via SSMS, use [Alter Table] Code instead';
RAISERROR(50001,16,1)
exec sp_dropmessage 50001
rollback;
end
END
Now Try alter Table1 Via SSMS designer from NULL to NOT NULL
The next pop messages will be raised:-