I've tried it. Pero yung pinaka need mo dapat naka Static yun Public IP mo which is available lang sa mga enterprise plans ni ISP.
Pero kung wala kang subscription plan na ganun, still possible pa rin with DDNS. Pero need mo ng isa pang router na may DDNS functions at dapat may full access ka rin sa ISP modem router to configure DMZ sa isang router. (matrabaho ito)
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Additional info lang, if for bussiness purpose yung pag expose mo SQL server mo that is good but may NOT be the best. I-scan lang ng häçker yung IP mo then kaya na nila malaman yung open port ng SQL server mo.
The best way to exposed your server is through VPN.