Grakn Console

Running Grakn Console in the terminal

Go to the directory whe you have your grakn-core-all or grakn-core-console distribution unarchived, and run ./grakn console

cd <your_grakn_console_dir>/
./grakn console

Command line arguments

You can provide several command arguments when running console in the terminal.

• --server=<address> : Grakn Core server address to which the console will connect to.
• --cluster=<address> : Grakn Cluster server address to which the console will connect to.
• --script=<script> : Run commands in the script file in non-interactive mode.
• -V, --version : Print version information and exit.
• -h, --help : Show help message.

Console commands

Grakn Console provides two levels of interaction: database-level commands and transaction-level commands. The database-level command is the first level of interaction, i.e. first-level REPL. From one of the database-level commands, you can open a transaction to the database. This will open a transaction-level interface, i.e. second-level REPL.

Database-level commands

• database create <db> : Create a database with name <db> on the server. For example:

  > database create my-grakn-database
  Database 'my-grakn-database' created
  

• database list : List the databases on the server. For example:

  > database list
  my-grakn-database
  

• database delete <db> : Delete a database with name <db> on the server. For example:

  > database delete my-grakn-database
  Database 'my-grakn-database' deleted
  

• transaction <db> schema|data read|write : Start a transaction to database <db> with session type schema or data, and transaction type write or read. For example:

  > transaction my-grakn-database schema write
  my-grakn-database::schema::write>
  

  This will then take you to the transaction-level interface, i.e. the second-level REPL.
• help : Print help menu
• clear : Clear console screen
• exit : Exit console

Transaction-level commands

• <query> : Once you're in the transaction REPL, the terminal immediately accepts a multi-line Graql query, and will execute it when you hit enter twice. For example:

  my-grakn-database::schema::write> define
                                    name sub attribute, value string;
                                    person sub entity, owns name;
  
  Concepts have been defined
  

• source <file> : Run Graql queries in a file, which you can refer to using relative or absolute path. For example:

  my-grakn-database::schema::write> source ./schema.gql
  Concepts have been defined
  

• commit : Commit the transaction changes and close transaction. For example:

  my-grakn-database::schema::write> commit
  Transaction changes committed
  

• rollback : Will remove any uncommitted changes you've made in the transaction, while leaving transaction open. For example:

  my-grakn-database::schema::write> rollback
  Rolled back to the beginning of the transaction
  

• close : Close the transaction without committing changes, and takes you back to the database-level interface, i.e. first-level REPL. For example:

  my-grakn-database::schema::write> close
  Transaction closed without committing changes
  

• help : Print this help menu
• clear : Clear console screen
• exit : Exit console

Scripting

To invoke console in a non-interactive manner, we can define a script file that contains the list of commands to run, then invoke console with ./grakn console --script=<script>.

For example given the following command script file:

database create test
transaction test schema write
    define person sub entity;
    commit
transaction test data write
    insert $x isa person;
    commit
transaction test data read
    match $x isa person;
    close
database delete test

You will see the following output:

> ./grakn console --script=script                                                                                                                                                                                                                    73.830s
+ database create test
Database 'test' created
+ transaction test schema write
++ define person sub entity;
Concepts have been defined
++ commit
Transaction changes committed
+ transaction test data write
++ insert $x isa person;
{ $x iid 0x966e80017fffffffffffffff isa person; }
answers: 1, duration: 87 ms
++ commit
Transaction changes committed
+ transaction test data read
++ match $x isa person;
{ $x iid 0x966e80018000000000000000 isa person; }
answers: 1, duration: 25 ms
++ close
Transaction closed without committing changes
+ database delete test
Database 'test' deleted

The indentation in the script file are only for visual guide and will be ignored by the console. Each line in the script is interpreted as one command, so multiline query is not available in this mode.