"to store and manage the databases of the client/server system, each server requires what"

A Data Base Management System (DBMS)

Explanation:

Databases refer to organized data collection mostly stored and accessed by computers and other electronic systems/devices. In other to effectively store, retrieve, manipulate/change data items in a database, a software package called a Data Base Management System (DBMS) is required. This software allows the manipulation, retrieval and general management of the data in the database. popular examples of DBMS are MySQL and Microsoft SQL Server. Therefore in a client/server system as stated in the this question, each server will require a DBMS installed to allow interaction with users and other applications, in order to capture, store, and manage data.

to change your username, you must:

1) make sure what the username you want to change to is allowed in this community

2) contact a administrator (for example, jaysl)

3) through pm, tell the admin what you want to change to

4) if the username is allowed, it will be changed in a matter of seconds (minutes at most)

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