In Windows Shared/Reseller hosting you can create MSSQL databases as per the resource allocated to your hosting plan.
You cannot create MSSQL database with unlimited size in Windows Shared/Reseller Hosting. If you need additional database storage space then you can contact our sales department.
VPS/Dedicated Server Hosting:
There is no restriction on number of database creation in Windows VPS/dedicated server. However, database size is limited based on the MSSQL server edition.
In Windows server, we provide MSSQL Server Express Edition, MSSQL Server Web Edition and MSSQL Server Standard (you will get an option to select it while placing an order). With MS SQL Server Express Edition (2008 R2/2012/2014), you can store up to 10 GB data. With MSSQL server web edition, you can store up to 524 PB.