PostgreSQL Extension

GART is supported as a PostgreSQL Extension. It is possible to operate the GART service through a PostgreSQL front-end such as psql.

Extension Installation

You need to install the PostgreSQL plugin by copying the shared library to the PostgreSQL library directory:

gart-env$ cd /workspace/gart/apps/pgx/
gart-env$ make USE_PGXS=1 -j
gart-env$ sudo make install

To enter commands into PostgreSQL, you need access to the PostgreSQL CLI. You can do this by opening a terminal on Unix-like systems or a command prompt on Windows, and running:

# choose the `ldbc` database
sudo -u postgres psql -d ldbc

# or
psql -U postgres -d ldbc

Extension Configuration

After successfully logging in to your database, run the following command to create the gart extension:

CREATE EXTENSION gart;

The gart extension has the following configuration options:

" The path of Kafka home and GART home
[path]
KAFKA_HOME=/path/to/kafka
GART_HOME=/path/to/gart

" The path of the log file and real-time log file
" Log file is used to record the log of the GART service after the service is started and stopped
" Real-time log file is used to record the log of the GART service in real time
[log]
log_path=/opt/postgresql/tmp.log
real_time_log_path=/opt/postgresql/gart.log

" The configuration of the GART service, as the arguments of the `gart` script
[gart]
db-type=postgresql
rgmapping-file=/opt/postgresql/rgmapping-ldbc.yaml
v6d-sock=/path/to/v6d.sock
etcd-endpoints=127.0.0.1:23760
etcd-prefix=gart_meta_
subgraph-num=1
enable-bulkload=1

Users can modify the configuration file to change the configuration of the GART service. The configuration file can be loaded as follows:

SELECT * FROM gart_set_config('/path/to/config.ini');

Extension Usage

Connection Building

-- Pull up the GART service under the current database with the current user
SELECT * FROM gart_get_connection('password');

-- Get the latest read-only epoch
SELECT * FROM gart_get_latest_epoch();

-- Exit GART server
SELECT * FROM gart_release_connection();

RGMapping Definition

We go through the SQL/PGQL language for the schema of the graph and the correspondence with the relational data source.

SELECT *
FROM gart_define_graph($$
                        CREATE TABLE Person (
                            p_id INT PRIMARY KEY,
                            p_name VARCHAR(100)
                        )
                    $$);

Graph Analytical Processing

Graph algorithms:

-- Initialize the graph server and return the server ID
SELECT * FROM gart_launch_graph_server('host', port);

-- Retrieve information about the graph server
SELECT * FROM gart_show_graph_server_info();

-- Terminate the server operation
SELECT * FROM gart_stop_graph_server(server_id);

-- Execute the Single Source Shortest Path query
SELECT * FROM gart_run_sssp(server_id, source_node);

Graph traversal:

SELECT *
FROM gart_query_by_gremlin($$
                        g.V().count()
                        $$);