Which of the following are true of databases that are used to support applications that are accessible through the Web? $($Check all that are true.$)$

a$.$

Because the web protocols are stateless there is a limited need to store data for web applications in databases.

b$.$

The user's web browser communicates with a web server and the web server communicates with the database, either directly or indirectly via web$-$to$-$database middleware $($also termed an application server$).$

c$.$

If the database supports a retail sales application, then it is critical that the database be designed for transaction rate scalability, because the number of visitors to the site can rise very quickly.

d$.$

Web databases always provide SQL access to web users so that they may manipulate data directly using SQL$.$