We are building a scheduling system for our startup. It's just an ordinary one, with people schedule, an opening/closure time for offices, etc. The idea is next: There're 3 main tables: - Offices - People - Schedule Offices table has open/close time for an office. Every single day of the year this time may be different. There're also 1000+ offices. This makes 365,000+ records in "Offices" table. People have join/leave times. Every single day of the year this time may be different. Each office has around 100 people. This makes 100*365*1000 = 36,500,000 records. Schedule is who will meet who. Each person may have around 500 schedules. Yes, this makes around 50 million rows. What the application needs to do is: given an office, person to meet and a duration, show first 5 dates available. By the way, just for the record, we've tried to develop it ourselves but DB stress is way too high. We are willing to pay for a better approach. Suggestions are also welcome. Keywords: Software, PHP, Architecture