Regarding the database, there is a 100,000, million database concept, may I ask what 100,000, million refers to?
number of data records, because, concurrency refers to the front part of the httpd, and concurrency does not cause a bottleneck in the database and then large database read and write can be read and write separation, non-timely update of the data can be resolved through the cache, 100,000, million-level database will be the existence of slow query problem, large amounts of data on the query, especially like the kind of link query and a variety of conditions of the query will be very slow slow slow which is the database The bottleneck of course can be divided into tables and other solutions.