SSIS .database files

ssis/ssis-dot-database-files.md

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+# SSIS .database files
+
+When you open an SSIS solution (aka `sln` file) a `database` file is expected to be in the same directory, and if it's not it will be automtically created.
+
+If you don't include the `*.database` in your VCS then some weird stuff can happen. When the ETL team at work migrated over to git last September we added `*.database` to the `.gitignore` file beliving that it wasn't something that should be source controlled. 
+
+What we've seen over the last several months are cases where a developer will open the solution, not make any changes, but git will recognize a change because of the `.database` file that was created and then linked up to the solution. 
+
+So I wanted to find out what exactly the `.database` file is, and what it does. 
+
+Per the [Micrsoft docs](https://learn.microsoft.com/en-us/sql/integration-services/integration-services-ssis-projects-and-solutions?view=sql-server-ver16&redirectedfrom=MSDN#files-in-integration-services-projects) this file
+
+> contains information that SQL Server Data Tools (SSDT) requires to open the Integration Services project.
+
+So, it's needed by the solution, but is also quite happy to create the file on the fly and cause weirdness with the git repo by reporting changes when there aren't any.
+
+The fix for this of course is to just make sure that the `.database` file is part of the repository initially, but what do you do if you added it to the `.gitignore` file like I did? 
+
+Here's what you can do to fix this for a single SSIS package:
+
+1. Update the `.dtproj` file to remove the <database> ... </database> section of the XML (don't worry, it's going to be recreated!) ... you can do this in an app like Notepad++
+2. Delete all of the `.database` files from the solution directory
+3. Open the Solution (`sln`) in Visual Studio
+
+Once that's done you should have a good `.database` file that doesn't have any extra numbers in the name of the file. 
+
+The next step is to remove the `*.database` from the `.gitignore` file since you'll want to have that be part of your source control
+
+Finally you'll add the changes you've made AND the `.database` file to your repository and commit them.
+
+Now when other ETL developers pull down the repository they won't have changes to the solution simply form opening it