I have read that to use ex. a relational D.B. we need a D.B server program and a D.B. client program (e.x. SQLdeveloper) which has a GUI for human to write his queries. When a web backend developer writes a PHP file which communicate with a D.B server program to create a dynamic web page by using a PDO object for example, Is there any need for a Database CLIENT program such as SQLdeveloper or something lighter? or the concept of Client-Server program doesn't have any meaning any more? I also read that PDO is a driver. Does it mean that it is equivalent to a light D.B client program?
Thanks for helping me to understand it