The mclient program is the universal command-line tool that implements the MAPI protocol for client-server interaction with MonetDB.
On a Windows platform it can be started using start->MonetDB->MonetDB SQL Client. Alternatively, you can use the command window to start mclient.exe. Be aware that your environment variables are properly set to find the libraries of interest.
On a Linux platform it provides readline functionality, which greatly improves user interaction. A history can be maintained to ease interaction over multiple sessions.
The default setting is geared at establishing a guest connection to a MonetDB SQL database server at a default server running on the localhost. The -h hostname specifies on which machine the MonetDB server is running. If you communicate with a MonetDB server on the same machine, it can be omitted. The default TCP port used is 50000. If this port happens to be in use on the server machine (which generally is only the case if you run two MonetDB servers on it), you will have to use the -p port do define the port to which the mserver is listening. Otherwise, it may also be omitted. If there is more than one mserver running, you must also specify the database name -d database. In this case, if your port is set to the wrong database, the connection will always be redirected to the correct one. Note that the default port (and other default options) can be set in the server configuration file.
shell>mclient --help
Usage: mclient [ options ] [ file or database [ file ... ] ]
Options are:
-h hostname | --host=hostname host or UNIX domain socket to connect to
-p portnr | --port=portnr port to connect to
-u user | --user=user user id
-d database | --database=database database to connect to (may be URI)
-e | --echo echo the query
-E charset | --encoding=charset specify encoding (character set) of the terminal
-f kind | --format=kind specify output format {csv,tab,raw,sql,xml,trash,rowcount}
-H | --history load/save cmdline history (default off)
-i | --interactive interpret `\' commands on stdin
-t | --timer=format use time formatting {none,clock,performance} (none is default)
-l language | --language=lang {sql,mal}
-L logfile | --log=logfile save client/server interaction
-s stmt | --statement=stmt run single statement
-X | --Xdebug trace mapi network interaction
-z | --timezone do not tell server our timezone
-| cmd | --pager=cmd for pagination
-v | --version show version information and exit
-? | --help show this usage message
SQL specific opions
-n nullstr | --null=nullstr change NULL representation for sql, csv and tab output modes
-a | --autocommit turn off autocommit mode
-R | --allow-remote allow remote content
-r nr | --rows=nr for pagination
-w nr | --width=nr for pagination
-D | --dump create an SQL dump
-N | --inserts use INSERT INTO statements when dumping
The file argument can be - for stdin
Within the context of each query language there are more options. They can be shown using the command \? or using the commandline.
For SQL there are several knobs to tune for a better rendering of result tables (\w).
shell>mclient -d demo
Welcome to mclient, the MonetDB/SQL interactive terminal (Oct2020)
Database: MonetDB v11.39.5 (Oct2020), 'demo'
FOLLOW US on https://twitter.com/MonetDB or https://github.com/MonetDB/MonetDB
Type \q to quit, \? for a list of available commands
auto commit mode: on
sql>\?
\? - show this message
\<file - read input from file
\>file - save response in file, or stdout if no file is given
\|cmd - pipe result to process, or stop when no command is given
\history - show the readline history
\help - synopsis of the SQL syntax
\D table - dumps the table, or the complete database if none given.
\d[Stvsfn]+ [obj] - list database objects, or describe if obj given
\A - enable auto commit
\a - disable auto commit
\e - echo the query in sql formatting mode
\t - set the timer {none,clock,performance} (none is default)
\f - format using renderer {csv,tab,raw,sql,xml,trash,rowcount,expanded}
\w# - set maximal page width (-1=unlimited, 0=terminal width, >0=limit to num)
\r# - set maximum rows per page (-1=raw)
\L file - save client-server interaction
\X - trace mclient code
\q - terminate session and quit mclient
sql>
