Best practice to store and execute a list of queries to build a Fact table Good afternoon,

Junior DBA/Developer here:

I have a DataMart that I have to build with a bunch of Statistical information. Each entry will be a different statistic and I have 80 different queries that will be executed on top of the DW to build the Fact table.

My question is on the best way to store, maintain and execute these queries. I have thought about storing them in different .sql files, storing them all together in a table (each entry is a query), or even managing them all in the same file with a giant UNION ALL putting them all together. This seems like a nightmare if not done right, and I don't really know how to proceed in doing this cleanly.
SSIS is included as part of your SQL Server license. Depending on the size, logical grouping, and dependencies I'd break the statements apart, into their own packages consisting of Execute SQL Tasks. Name these appropriately to what they're doing! It will assist in maintenance and trouble-shooting.

Create a Master Package that uses an Execute Package Task to individually call your T-SQL execution packages. This allows clean way that anyone can see the order, or parallelism, of your process. It also gives you a single package to schedule and view native SSIS reports from.

Additionally, all of these tasks can now be stored in a single Visual Studio (SSDT) project and should ideally be stored in source control. Ensure you download the appropriate version of BI tools for SQL Server Data Tools for your server version... they have backwards compatibility issues when deploying SSIS projects.

There are plenty of resources for master package design and such... this should set you on the right path for additional binging.