有什么方法可以在SSDT数据库项目中引用CDC对象？

Question

I'm trying to create a database project from an extant database. Some of the tables in the database have CDC enabled. For each such table, we've created a view into the CDC data that looks something like:

create view [dbo].[vw_cdc_myTable] as
select 
   sys.fn_cdc_map_lsn_to_time (__$start_lsn) ActionLocalTime
   ,    __$seqval ActionOrder
   ,    __$operation ImageType
   ,    case __$operation
            when 1 then 'Deleted'
            when 2 then 'Inserted'
            when 3 then 'Before Update'
            when 4 then 'After Update'
        end ImageType_desc
   ,    convert(char(5), '>>>>>') Sprtr
   ,    *
from 
    cdc.dbo_myTable_CT

SSDT complains about this as it didn't import any of the CDC objects (in this case, cdc.dbo_myTable_CT and sys.fn_cdc_map_lsn_to_time). Is there any way to either have those imported or to fake SSDT out so that I can have the view in source control?

Answer 1

Yes, there's a way to do it. It's called cheating, but it works wonders.

Follow these steps:

1. Create a stub SSDT project in your solution and call it CDC (or whatever placeholder name you want)
2. Add a schema object to that fake project, named [cdc]
3. Script out the CREATE of your dbo_myTable_CT and add it as a table object to your fake project
4. Now the fun begins: Add that fake a project as a database reference to your main project, and name the SQLCMD variable for the reference as CDC (for example)
5. Change the from clause in your view to look like this:

   \n\n    from [$(CDC)].cdc.dbo_myTable_CT \n\n

6. Now, when you are deploying your database, when asked for the actual name for the CDC database, just use the same database name in your own project. They are the same database, technically. You main code will be deployed, while the cdc table in the target won't be touched.

That's it!

You can also use this trick to make deployment ignore publishing of certain objects altogether while still husing them in some way.