Architecture of the Database Tools 
Some SAP MaxDB database tools are available in several variants. And some database tools are comprised of multiple components.
If a database tool is on a different computer than the database, the database system also needs the SAP MaxDB X Server (communication server) for communication.
More information: X Server documentation
DBM Server
The DBM server is the server via which administration commands are executed. The database tools Database Studio, Database Manager and Event Dispatcher use the DBM server. The DBM server always resides on the same computer as the database.
Database Studio
Database Studio uses the JDBC interface to communicate with the X Server. The JDBC interface is always on the same computer as Database Studio, and the X Server is on the same database computer. Note that the JDBC interface and thus Database Studio needs the X Server even if it is installed on the same computer as the database.
Database Studio Architecture
Database Manager
Database Manager consists of a client part and a server part. The client part of Database Manager is available in several variants:
Database Manager CLI (DBMCLI): Command line interface
Database Manager RFC (DBMRFC): Only in SAP systems, interface to the SAP system
Database Manager GUI (DBMGUI): Graphical user interface
If the client part of Database Manager and the database instance are located on different computers, you also need the X Server for communication.
Architecture of the Database Manager
Query Tools
Query tools are database tools with which you can execute SQL statements. They come in three variants:
Web SQL Studio: Web-based user interface
SQLCLI: Command line interface
SQL Studio: Graphical user interface
Note
You can also execute SQL statements using Database Studio.
Web SQL communicates with the database kernel via the servlet container (for example Apache Tomcat or SAP NetWeaver AS); SQL Studio communicates with the database kernel through the ODBC interface; and SQLCLI communicates with the database kernel via SQLDBC. If the database tools are on a different computer than the database, they also need the X Server to communicate with the database.
Architecture of the Query Tools
Loader
Loader consists of a client part and a server part:
Loader client
Loader server
The Loader client transmits the commands that are to be processed. The Loader server creates the connection between the Loader client and the database, and processes the commands. The Loader client and the Loader server are always installed on the same computer (LoaderCLI).
You can access Loader using the following interfaces:
Python module: sdb.loader
Perl module: SAP::DBTech::loader
Java interface of Loader: com.sap.dbtech.powertoys.Loader
If you use files as data carriers for exporting or importing data we recommend that you install the Loader server on the computer on which the data is located.
If Loader is on a different computer than the database, Loader also needs the X Server to communicate with the database.
Architecture of Loader
XUSER
XUSER does not communicate directly with other database tools or the database kernel; it only writes XUSER information to the file system. Database tools that use XUSER directly access the XUSER information in the file system.
Architecture of XUSER
Other Database Tools
XCONS communicates directly with the database kernel. It must be installed on the same computer as the database.
Database Analyzer communicates with the database kernel using ODBC. If Database Analyzer is on a different computer than the database, Database Analyzer also needs the X Server to communicate with the database.
Architecture of Other Database Tools