Obtaining Help Information

Procedure

When connecting to the database, run the following command to obtain the help information:

gsql --help

The following help information is displayed:

......
Usage:
  gsql [OPTION]... [DBNAME [USERNAME]]

General options:
  -c, --command=COMMAND    run only single command (SQL or internal) and exit
  -d, --dbname=DBNAME      database name to connect to (default: "omm")
  -f, --file=FILENAME      execute commands from file, then exit
......

When connecting to the database, run the following command to obtain the help information:

help

The following help information is displayed:

You are using gsql, the command-line interface to gaussdb.
Type:  \copyright for distribution terms
       \h for help with SQL commands
       \? for help with gsql commands
       \g or terminate with semicolon to execute query
       \q to quit

Examples

Run the following command to connect to the database:
```
gsql -d postgres -p 8000
```
postgres is the name of the database to be connected, and 8000 is the port number of the database primary node.
If information similar to the following is displayed, the connection succeeds:
```
gsql ((openGauss VxxxRxxxCxx build 290d125f) compiled at 2020-05-08 02:59:43 commit 2143 last mr 131)
Non-SSL connection (SSL connection is recommended when requiring high-security)
Type "help" for help.
```

View the gsql help information. For details, see Table 1.

Table 1 gsql online help

Description	Example
Query the copyright.	\copyright
View help information about SQL statements supported by openGauss.	View help information about SQL statements supported by openGauss. For example, view all SQL statements supported by openGauss. openGauss=# \h Available help: ABORT ALTER AGGREGATE ALTER APP WORKLOAD GROUP ... ... For example, view parameters of the CREATE DATABASE command: openGauss=# \help CREATE DATABASE Command: CREATE DATABASE Description: create a new database Syntax: CREATE DATABASE database_name [ [ WITH ] {[ OWNER [=] user_name ]\| [ TEMPLATE [=] template ]\| [ ENCODING [=] encoding ]\| [ LC_COLLATE [=] lc_collate ]\| [ LC_CTYPE [=] lc_ctype ]\| [ DBCOMPATIBILITY [=] compatibility_type ]\| [ TABLESPACE [=] tablespace_name ]\| [ CONNECTION LIMIT [=] connlimit ]}[...] ];
View the help information about gsql commands.	For example, view commands supported by gsql. openGauss=# \? General \copyright show openGauss usage and distribution terms \g [FILE] or ; execute query (and send results to file or \|pipe) \h(\help) [NAME] help on syntax of SQL commands, * for all commands \q quit gsql ... ...

Description

Example

Query the copyright.

\copyright

View help information about SQL statements supported by openGauss.

For example, view all SQL statements supported by openGauss.

openGauss=# \h
Available help:
  ABORT                            
  ALTER AGGREGATE
  ALTER APP WORKLOAD GROUP                  
... ...

For example, view parameters of the CREATE DATABASE command:

openGauss=# \help CREATE DATABASE
Command:     CREATE DATABASE
Description: create a new database
Syntax:
CREATE DATABASE database_name
     [ [ WITH ] {[ OWNER [=] user_name ]|
           [ TEMPLATE [=] template ]|
           [ ENCODING [=] encoding ]|
           [ LC_COLLATE [=] lc_collate ]|
           [ LC_CTYPE [=] lc_ctype ]|
           [ DBCOMPATIBILITY [=] compatibility_type ]|
           [ TABLESPACE [=] tablespace_name ]|
           [ CONNECTION LIMIT [=] connlimit ]}[...] ];

View the help information about gsql commands.

For example, view commands supported by gsql.

openGauss=# \?
General
  \copyright             show openGauss usage and distribution terms
  \g [FILE] or ;         execute query (and send results to file or |pipe)
  \h(\help) [NAME]              help on syntax of SQL commands, * for all commands
  \q                     quit gsql
... ...