Step 1: Startup

xSQL is an interactive tool for processing SQL statements. It can be run as a server to provide access to eXtremeDB databases from local or remote clients. For example from directory target/bin type the following command to open an in-memory database with size 100 Mb and start a server session listening on port 5000 of the host computer:

 
    xsql -size 100m -p 5000
     

xSQL responds with the line

     
    press Enter to stop SQL server
     

indicating that it is running in server mode. A client can be another instance of xSQL that connects to the port specified by the server, or it can be any application using the eXtremeSQL API. To start xSQL as a client process on the same host computer, connecting to the server instance above, use the following command:

 
    xsql @127.0.0.1:5000
     

xSQL responds with the following lines indicating that it is in client mode, ready to accept interactive commands:

     
    xsql started
    Runtime configuration
     Remote node(s)        : 127.0.0.1:5000
     Runtime                          : Release
    XSQL>
     

To end the client/server session, first close the client by typing the command exit.

 
    XSQL>exit
     

Then close the server by pressing <Enter>.

xSQL can be opened in a single interactive server process, so that a separate client process is not necessary, by simply typing xsql from directory target/bin:

 
    xsql
     
    Simple interactive configuration is started
    To run as a server, type, for example: 'xsql -size 100m -p 5000'
    Then to connect as a client, use 'xsql @127.0.0.1:5000'
    Type 'xsql -h' for more details
     
    xsql started
    Runtime configuration
      Transaction manager  : MURSIW
     Storage (transient)  : Conventional memory, 100M
     Storage (persistent) : Not supported
     Runtime                     : Release
    XSQL>
     

Note that, if no command line arguments are specified the default options are equivalent to running with the command line xsql –i –size 100m. As the display indicates, xSQL is running in interactive mode with the following characteristics:

• 100 Megabytes for database storage - the space to be allocated for the database.
• MURSIW is the transaction manager
• transient database objects will be created in conventional memory (RAM)
• persistent (disk-based) database objects are not supported
• the eXtremeDB release mode libraries are loaded

(Note that xSQL can be started with a variety of command-line configuration options, including the -c option to read configuration specifications from a config.file, in addition to the “server” and “client” examples above. All command-line options and configuration file specifications can be viewed here.)

Now we can execute SQL commands interactively. Use this link to view some examples.