Nebula Console¶
Nebula Console is a native CLI client for NebulaGraph. It can be used to connect a NebulaGraph cluster and execute queries. It can also support special commands to manage parameters, export query results, import test datasets, etc. This topic describes these special commands.
To connect NebulaGraph using Nebula Console, see Step 3: Connect to NebulaGraph.
Note
The commands are case insensitive.
Manage parameters¶
You can save parameters for parameterized queries.
Note
- Setting a parameter as a VID in a query is not supported.
- Parameters are not supported in
SAMPLE
clauses.
- Parameters are deleted when their sessions are released.
-
The command to save a parameter is as follows:
nebula> :param <param_name> => <param_value>;
The example is as follows:
nebula> :param p1 => "Tim Duncan"; nebula> MATCH (v:player{name:$p1})-[:follow]->(n) RETURN v,n; +----------------------------------------------------+-------------------------------------------------------+ | v | n | +----------------------------------------------------+-------------------------------------------------------+ | ("player100" :player{age: 42, name: "Tim Duncan"}) | ("player125" :player{age: 41, name: "Manu Ginobili"}) | | ("player100" :player{age: 42, name: "Tim Duncan"}) | ("player101" :player{age: 36, name: "Tony Parker"}) | +----------------------------------------------------+-------------------------------------------------------+ nebula> :param p2 => {"a":3,"b":false,"c":"Tim Duncan"}; nebula> RETURN $p2.b AS b; +-------+ | b | +-------+ | false | +-------+
-
The command to view the saved parameters is as follows:
nebula> :params;
-
The command to delete a specified parameter is as follows:
nebula> :param <param_name> =>;
Export query results¶
Export query results, which can be saved as a CSV file or DOT file.
Note
- The exported file is stored in the working directory, i.e., what the linux command
pwd
shows.
- This command only works for the next query statement.
- You can copy the contents of the DOT file and paste them in GraphvizOnline to generate a visualized execution plan.
-
The command to export a csv file is as follows:
nebula> :CSV <file_name.csv>;
-
The command to export a DOT file is as follows:
nebula> :dot <file_name.dot>
The example is as follows:
nebula> :dot a.dot nebula> PROFILE FORMAT="dot" GO FROM "player100" OVER follow;
Import a testing dataset¶
The testing dataset is named basketballplayer
. To view details about the schema and data, use the corresponding SHOW
command.
The command to import a testing dataset is as follows:
nebula> :play basketballplayer
Run a command multiple times¶
To run a command multiple times, use the following command:
nebula> :repeat N
The example is as follows:
nebula> :repeat 3
nebula> GO FROM "player100" OVER follow YIELD dst(edge);
+-------------+
| dst(EDGE) |
+-------------+
| "player101" |
| "player125" |
+-------------+
Got 2 rows (time spent 2602/3214 us)
Fri, 20 Aug 2021 06:36:05 UTC
+-------------+
| dst(EDGE) |
+-------------+
| "player101" |
| "player125" |
+-------------+
Got 2 rows (time spent 583/849 us)
Fri, 20 Aug 2021 06:36:05 UTC
+-------------+
| dst(EDGE) |
+-------------+
| "player101" |
| "player125" |
+-------------+
Got 2 rows (time spent 496/671 us)
Fri, 20 Aug 2021 06:36:05 UTC
Executed 3 times, (total time spent 3681/4734 us), (average time spent 1227/1578 us)
Sleep to wait¶
This command will make NebulaGraph services sleep and wait for N seconds. The schema is altered in an async way and takes effect in the next heartbeat cycle. Therefore, this command is usually used when altering schema. The command is as follows:
nebula> :sleep N
Disconnect Nebula Console from NebulaGraph¶
You can use :EXIT
or :QUIT
to disconnect from NebulaGraph. For convenience, Nebula Console supports using these commands in lower case without the colon (":"), such as quit
.
The example is as follows:
nebula> :QUIT
Bye root!
FAQ¶
"How can I install Nebula Console from the source code?"¶
To download and compile the latest source code of Nebula Console, follow the instructions on the nebula console GitHub page.