I'm thinking about buying a shared hosting provider, and then offer a 1GB MSSQL database with the package.
This may not be an exact science, but how many records/tables can I save in a 1GB database? I will be saving pure text (meaning: nvarchar, varchar, int, bool) and not binaries/blobs.
For this question, imagine around 20 tables, with 9 fields each. Not null on every field.
Is there some way to gauge and project how long this will hold me over before I need to upgrade to a more expensive package?
There is no real answer that tells you 'set amount' of 'records and/or tables' is the maximum that you can hold in a 1 GB MSSQL database, or when you'll reach that point. There are several factors to look at when estimating:
In the end, you're looking at (for example) a maximum amount of rows that could be < 400 000 rows or > 3 500 000, it all comes down to what you put in a single row and what types you're using. Once you have decided what a single row will be (give or take) and how many rows you're expecting to be added/frequency, you can determine how long you'll be able to go without upgrading to another database package.