use variable in sql trigger creation

I'm trying to create a trigger dynamically and need to replace part of the create statement, in particular the database name that a join is done on.

CREATE TRIGGER [dbo].[tr_UseType_update] ON [dbo].[UseType] FOR UPDATE AS
BEGIN
  SET NOCOUNT ON 
  INSERT [dbo].[UseType]
  SELECT 'Updated', i.*
    FROM inserted
   INNER JOIN [(SELECT DB_NAME())].[dbo].[UseType] i ON inserted.[UseTypeID] 开发者_运维知识库= i.[UseTypeID]
END

I've tried this but obviously it just uses the text it doesn't actually evaluate SELECT DB_NAME(), is there a way to get it to evaluate this value.

I'm using sql 2005/8. We have a deployment tool that uses sqlcmd so a fallback will be to change the tool to take in variables that can be passed to sqlcmd but if I can reduce the amount of work and do it in the script itself (which is generated) that would be handy.

The only way would be to use dynamic sql.

There's no other way to parameterize database names or table names.

That being said, dynamically creating a trigger like this seems like a perilous idea.

The easiest way to do what you want will be something like:

USE MyDataBase

DECLARE @DB varchar(100) = 'MyOtherDatabaseThatIAmJoiningToInTheInsert'
DECLARE @SQL Varchar (MAX)

SET @SQL = '
CREATE TRIGGER [dbo].[tr_UseType_update] ON [dbo].[UseType] FOR UPDATE AS
BEGIN
  SET NOCOUNT ON 
  INSERT [dbo].[UseType]
  SELECT ''Updated'', i.*
    FROM inserted
   INNER JOIN ' + @DB + '.[dbo].[UseType] i ON inserted.[UseTypeID] = i.[UseTypeID]
END'

It's mandatory to read this before doing any dynamic sql code, though!

You could potentially execute dynamic sql and load that into a temp table which in turn would be available to the trigger.

CREATE TRIGGER [dbo].[tr_UseType_update] ON [dbo].[UseType]
    FOR UPDATE
AS
    BEGIN
        SET NOCOUNT ON
        CREATE TABLE #t (userTypeId INT)
        DECLARE @sql NVARCHAR(500) SET @sql = 'insert into #t select userTypeID from ' + DB_NAME() + '.dbo.UseType'
        EXEC sp_executeSQL @sql

        INSERT  [dbo].[UseType]
                SELECT  'Updated',
                        i.*
                FROM    inserted
                        INNER JOIN #t i ON inserted.[UseTypeID] = i.[UseTypeID]
    END