Install Sql Server Express programatically

Hello All,

I have an requirement to create an installer for installing MS Sql Server Express and databse. Basically we have a web application which done MS SQL for database transaction but before running application sql express should be installed at client end but sometime it's installation is very hectic user hence to avoid this our application will install SQL Express on its unavailabilty just like Autodesk Vault Installer so could anyone tell me how to install SQL Server programatically.

Thanks & Regards,
Rupali
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