Meta-Command Reference

\copyright

Displays GaussDB version and copyright information.

-

\g [FILE] or ;

Performs a query operation and sends the result to a file or pipe.

-

\h(\help) [NAME]

Provides syntax help on the specified SQL statement.

If the name is not specified, then gsql will list all the commands for which syntax help is available. If the name is an asterisk (*), syntax help on all SQL statements is displayed.

\parallel [on [num]|off]

Controls the parallel execution function.

• on: The switch is enabled and the maximum number of concurrently executed tasks is num.
• off: This switch is disabled.

The default value of num is 1024.

\q

Exits the gsql program. This command is executed only when a script terminates in a script file.

-

\e [FILE] [LINE]

Uses an external editor to edit the query buffer or file.

\ef [FUNCNAME [LINE]]

Edits the function definition using an external editor. If LINE is specified, the cursor will point to the specified line of the function body.

\p

Prints the current query buffer to the standard output.

\r

Resets or clears the query buffer.

\w FILE

Outputs the current query buffer to a file.

\copy { table [ ( column_list ) ] | ( query ) } { from | to } { filename | stdin | stdout | pstdin | pstdout } [ with ] [ binary ] [ oids ] [ delimiter [ as ] 'character' ] [ useeof ] [ null [ as ] 'string' ] [ csv [ header ] [ quote [ as ] 'character' ] [ escape [ as ] 'character' ] [ force quote column_list | * ] [ force not null column_list ] ] [parallel integer]

After logging in to the database on any gsql client, you can import and export data. This is an operation of running the SQL COPY command, but not the server that reads or writes data to a specified file. Instead, data is transferred between the server and the local file system. In this way, local user permissions instead of server permissions are required for file access, and the user permissions do not need to be initialized.

\echo [STRING]

Writes character strings to the standard output.

\i FILE

Reads content from FILE and uses them as the input for a query.

\i+ FILE KEY

Runs commands in an encrypted file.

\ir FILE

Similar to \i, but resolves relative path names differently.

\ir+ FILE KEY

Similar to \i+, but resolves relative path names differently.

\o [FILE]

Saves all query results to a file.

\qecho [STRING]

Writes character strings to the query output flow.

\d[S+]

Lists all tables, views, and sequences of all schemas in the search_path. When objects with the same name exist in different schemas in search_path, only the object in the schema that ranks first in search_path is displayed.

-

Lists all tables, views, and sequences of all schemas in the search_path.

1

openGauss=# \d

\d[S+] NAME

Lists the structure of specified tables, views, and indexes.

-

Lists the structure of table a.

1

openGauss=# \dtable+ a

\d+ [PATTERN]

Lists all tables, views, and indexes.

If PATTERN is specified, only tables, views, and indexes whose names match PATTERN are displayed.

Lists all tables, views, and indexes whose names start with f.

1

openGauss=# \d+ f*

\da[S] [PATTERN]

Lists all available aggregate functions, together with the data type they perform operations on and the return value types.

If PATTERN is specified, only aggregate functions whose names match PATTERN are displayed.

Lists all available aggregate functions whose names start with f, together with their return value types and the data types.

1

openGauss=# \da f*

\db[+] [PATTERN]

Lists all available tablespaces.

If PATTERN is specified, only tablespaces whose names match PATTERN are displayed.

Lists all available tablespaces whose names start with p.

1

openGauss=# \db p*

\dc[S+] [PATTERN]

Lists all available conversions between character-set encodings.

If PATTERN is specified, only conversions whose names match PATTERN are displayed.

Lists all available conversions between character-set encodings.

1

openGauss=# \dc *

\dC[+] [PATTERN]

Lists all available type conversions.

PATTERN must be the actual type name and cannot be an alias.

If PATTERN is specified, only conversions whose names match PATTERN are displayed.

Lists all type conversions whose patten names start with c.

1

openGauss=# \dC c*

\dd[S] [PATTERN]

Lists descriptions about objects matching PATTERN.

If no parameter is specified, all visible objects are displayed. The objects include aggregations, functions, operators, types, relations (tables, views, indexes, sequences, and large objects), and rules.

Lists all visible objects.

1

openGauss=# \dd

\ddp [PATTERN]

Lists all default permissions.

If PATTERN is specified, only permissions whose names match PATTERN are displayed.

Lists all default permissions.

1

openGauss=# \ddp

\dD[S+] [PATTERN]

Lists all available domains.

If PATTERN is specified, only domains whose names match PATTERN are displayed.

Lists all available domains.

1

openGauss=# \dD

\ded[+] [PATTERN]

Lists all Data Source objects.

If PATTERN is specified, only objects whose names match PATTERN are displayed.

Lists all Data Source objects.

1

openGauss=# \ded

\det[+] [PATTERN]

Lists all external tables.

If PATTERN is specified, only tables whose names match PATTERN are displayed.

Lists all external tables.

1

openGauss=# \det

\des[+] [PATTERN]

Lists all external servers.

If PATTERN is specified, only servers whose names match PATTERN are displayed.

Lists all external servers.

1

openGauss=# \des

\deu[+] [PATTERN]

Lists all user mappings.

If PATTERN is specified, only information whose name matches PATTERN is displayed.

Lists all user mappings.

1

openGauss=#\deu

\dew[+] [PATTERN]

Lists all encapsulated external data.

If PATTERN is specified, only data whose name matches PATTERN is displayed.

Lists all encapsulated external data.

1

openGauss=# \dew

\df[antw][S+] [PATTERN]

Lists all available functions, together with their parameters and return types. a indicates an aggregate function, n indicates a common function, t indicates a trigger, and w indicates a window function.

If PATTERN is specified, only functions whose names match PATTERN are displayed.

Lists all available functions, together with their parameters and return types.

1

openGauss=# \df

\dF[+] [PATTERN]

Lists all text search configuration information.

If PATTERN is specified, only configurations whose names match PATTERN are displayed.

Lists all text search configuration information.

1

openGauss=# \dF+

\dFd[+] [PATTERN]

Lists all text search dictionaries.

If PATTERN is specified, only dictionaries whose names match PATTERN are displayed.

Lists all text search dictionaries.

1

openGauss=# \dFd

\dFp[+] [PATTERN]

Lists all text search analyzers.

If PATTERN is specified, only analyzers whose names match PATTERN are displayed.

Lists all text search analyzers.

1

openGauss=# \dFp

\dFt[+] [PATTERN]

Lists all text search templates.

If PATTERN is specified, only templates whose names match PATTERN are displayed.

Lists all text search templates.

1

openGauss=# \dFt

\dg[+] [PATTERN]

Lists all database roles.

If PATTERN is specified, only roles whose names match PATTERN are displayed.

Lists all database roles named j?e (the question mark (?) indicates any character).

1

openGauss=# \dg j?e

\dl

This is an alias for \lo_list, which shows a list of large objects.

-

Lists all large objects.

1

openGauss=# \dl

\dL[S+] [PATTERN]

Lists all available program languages.

If PATTERN is specified, only languages whose names match PATTERN are displayed.

Lists all available program languages.

1

openGauss=# \dL

\dm[S+] [PATTERN]

Lists materialized views.

If PATTERN is specified, only materialized views whose names match PATTERN are displayed.

Lists materialized views.

1

openGauss=# \dm

\dn[S+] [PATTERN]

Lists all schemas (namespace). If + is added to the command, the permission and description of each schema are listed.

If PATTERN is specified, only schemas whose names match PATTERN are displayed. By default, only schemas you created are displayed.

Lists information about all schemas whose names start with d.

1

openGauss=# \dn+ d*

\do[S] [PATTERN]

Lists available operators with their operand and return types.

If PATTERN is specified, only operators whose names match PATTERN are displayed. By default, only the operators created by the user are listed.

Lists available operators with their operand and return types.

1

openGauss=# \do

\dO[S+] [PATTERN]

Lists collation rules.

If PATTERN is specified, only rules whose names match PATTERN are displayed. By default, only user-created rules are shown.

Lists collation rules.

1

openGauss=# \dO

\dp [PATTERN]

Lists tables, views, and related permissions.

The following result about \dp is displayed:

rolename=xxxx/yyyy  --Assigns permissions to a role.

=xxxx/yyyy --Assigns permissions to public.

xxxx indicates the assigned permissions, and yyyy indicates the roles with the assigned permissions. For details about permission descriptions, see Table 5.

If PATTERN is specified, only tables and views whose names match PATTERN are displayed.

Lists tables, views, and related permissions.

1

openGauss=# \dp

\drds [PATTERN1 [PATTERN2]]

Lists all parameters that have been modified. These settings can be for roles, for databases, or for both. PATTERN1 and PATTERN2 indicate a role pattern and a database pattern, respectively.

If PATTERN is specified, only collations rules whose names match PATTERN are displayed. If the default value is used or * is specified, all settings are listed.

Lists all the modified configuration parameters of the database.

1

openGauss=# \drds * dbname

\dT[S+] [PATTERN]

Lists all data types.

If PATTERN is specified, only types whose names match PATTERN are displayed.

Lists all data types.

1

openGauss=# \dT

\du[+] [PATTERN]

Lists all database roles.

If PATTERN is specified, only roles whose names match PATTERN are displayed.

Lists all database roles.

1

openGauss=# \du

\dE[S+] [PATTERN]

\di[S+] [PATTERN]

\ds[S+] [PATTERN]

\dt[S+] [PATTERN]

\dv[S+] [PATTERN]

In this group of commands, the letters E, i, s, t, and v stand for foreign table, index, sequence, table, and view, respectively. You can specify any or a combination of these letters sequenced in any order to obtain an object list. For example, \dit lists all indexes and tables. If + is added to the end of a command name, the physical size and related description of each object are also listed.

If PATTERN is specified, only objects whose names match PATTERN are displayed. By default, only objects you created are displayed. You can specify PATTERN or S to view other system objects.

Lists all indexes and views.

1

openGauss=# \div

\dx[+] [PATTERN]

Lists installed extensions.

If PATTERN is specified, only extensions whose names match PATTERN are displayed.

Lists installed extensions.

1

openGauss=# \dx

\l[+]

Lists the names, owners, character set encodings, and permissions of all the databases in the server.

-

List the names, owners, character set encodings, and permissions of all the databases in the server.

1

openGauss=# \l

\sf[+] FUNCNAME

Displays the definition of a function.

-

Assume a function function_a and a function func()name. This parameter will be as follows:

1
2
3

openGauss=# \sf function_a
openGauss=# \sf 
"func()name"(argtype1, argtype2)

\z [PATTERN]

Lists all tables, views, and sequences in the database and their access permissions.

If a pattern is given, it is a regular expression, and only matched tables, views, and sequences are shown.

Lists all tables, views, and sequences in the database and their access permissions.

1

openGauss=# \z

r

SELECT: allows users to read data from specified tables and views.

w

UPDATE: allows users to update columns for specified tables.

a

INSERT: allows users to insert data to specified tables.

d

DELETE: allows users to delete data from specified tables.

D

TRUNCATE: allows users to delete all data from specified tables.

x

REFERENCES: allows users to create foreign key constraints.

t

TRIGGER: allows users to create a trigger on specified tables.

X

EXECUTE: allows users to use specified functions and the operators that are realized by the functions.

U

USAGE:

• For procedural languages, allows users to specify a procedural language when creating a function.
• For schemas, allows users to access objects included in specified schemas.
• For sequences, allows users to use the nextval function.

C

CREATE:

• For databases, allows new schemas to be created within the database.
• For schemas, allows users to create objects in a schema.
• For tablespaces, allows users to create tables in a tablespace and set the tablespace to default one when creating databases and schemas.

c

CONNECT: allows users to connect to specified databases.

T

TEMPORARY: allows users to create temporary tables.

A

ALTER: allows users to modify the attributes of a specified object.

P

DROP: allows users to delete specified objects.

m

COMMENT: allows users to define or modify comments of a specified object.

i

INDEX: allows users to create indexes on specified tables.

v

VACUUM: allows users to perform ANALYZE and VACUUM operations on specified tables.

*

Authorization options for preceding permissions.

\a

Switches between aligned and unaligned table output formats.

\C [STRING]

Sets the title of any table being printed as the result of a query or cancels such a setting.

\f [STRING]

Sets the field separator for unaligned query outputs.

\H

• If the text format schema is used, switches to the HTML format.
• If the HTML format schema is used, switches to the text format.

\pset NAME [VALUE]

Sets options affecting the output of query result tables. For details about the value of NAME, see Table 7.

\t [on|off]

Switches the display of output name information and row count footer.

\T [STRING]

Specifies attributes to be placed within the table tag in HTML output format. If this parameter is empty, no attribute is specified.

\x [on|off|auto]

Switches expanded table formatting mode.

border

The value must be a number. In general, the larger the number, the more borders and lines the tables will have, but this depends on the particular format.

• The value is an integer greater than 0 in HTML format.
• The value range in other formats is as follows:
  • 0: no border
  • 1: internal dividing line
  • 2: table frame

expanded (or x)

Switches between regular and expanded formats.

• When the expanded format is enabled, query results are displayed in two columns, with the column name on the left and the data on the right. This format is useful if the data does not fit the screen in the normal "horizontal" format.
• Use the expanded format when the query output format is wider than the screen in regular format. The regular format is effective only in the aligned and wrapped formats.

fieldsep

Specifies the field separator to be used in unaligned output mode. In this way, you can create tab- or comma-separated output required by other programs. To set a tab as field separator, type \pset fieldsep '\t'. The default field separator is a vertical bar (|).

-

fieldsep_zero

Sets the field separator to use in unaligned output format to a zero byte.

-

footer

Switches the display of the default footer.

-

format

Selects the output format. Unique abbreviations are allowed (this indicates that one letter is enough).

Value range:

• unaligned: Write all columns of a row on one line, separated by the currently active column separator.
• aligned: This format is standard and human-readable.
• wrapped: This format is similar to aligned, but includes the packaging cross-line width data value to suit the width of the target field output.
• html: This format outputs tables to the markup language for a document. The output is not a complete document.
• latex: This format outputs tables to the markup language for a document. The output is not a complete document.
• troff-ms: This format outputs tables to the markup language for a document. The output is not a complete document.

null

Sets a character string to be printed in place of a null value.

The default is to print nothing, which can be easily mistaken for an empty string.

numericlocale

Switches the display of a locale-aware character to separate groups of digits to the left of the decimal marker.

• on: The specified separator is displayed.
• off: The specified separator is not displayed

If this parameter is ignored, the default separator is displayed.

pager

Controls the use of a pager for query and gsql help outputs. If the PAGER environment variable is set, the output is redirected to the specified program. Otherwise, the platform-dependent default value is used.

• on: The pager is used for terminal output that does not fit the screen.
• off: The pager is not used.
• always: The pager is used for all terminal output regardless of whether it fits the screen.

recordsep

Specifies the record separator to use in unaligned output mode.

-

recordsep_zero

Sets the record separator to use in unaligned output format to a zero byte.

-

tableattr (or T)

Specifies attributes to be placed inside the HTML table tag in HTML output format (such as cellpadding or bgcolor). Note that you do not need to specify border here because it has been used by \pset border. If no value is given, the table attributes do not need to be set.

-

title

Sets the table title for any subsequently printed tables. This can be used to give your output descriptive tags. If no value is given, the title does not need to be set.

-

tuples_only (or t)

Enables or disables the tuples-only mode. Full display may show extra information, such as column headers, titles, and various footers. In tuples-only mode, only the table data is shown.

-

feedback

Specifies whether to output the number of result lines.

-

\c[onnect] [DBNAME|- USER|- HOST|- PORT|-]

Connects to a new database. If a database name contains more than 63 bytes, only the first 63 bytes are valid and are used for connection. However, the database name displayed in the command line of gsql is still the name before the truncation.

-

\encoding [ENCODING]

Sets the client character set encoding.

Without an argument, this command shows the current encoding.

\conninfo

Prints information about the current connected database.

-

\cd [DIR]

Changes the current working directory.

An absolute path or relative path that meets the OS path naming convention

\setenv NAME [VALUE]

Sets the NAME environment variable to VALUE. If VALUE is not provided, do not set the environment variable.

-

\timing [on|off]

Displays how long each SQL statement takes, in milliseconds.

• on: specifies that the display is enabled.
• off: indicates that the display is disabled.

\! [COMMAND]

Escapes to a separate Unix shell or runs a Unix command.

-

\prompt [TEXT] NAME

Prompts the user to use texts to specify a variable name.

\set [NAME [VALUE]]

Sets the NAME internal variable to VALUE. If more than one value is provided, NAME is set to the concatenation of all of them. If no second argument is given, the variable is just set with no value.

Some common variables are processed differently in gsql and they are combinations of uppercase letters, numbers and underscores. Table 11 describes a list of variables that are processed in a way different from other variables.

\unset NAME

Deletes the variable name of gsql.

\set VERBOSITY value

This variable can be set to default, verbose, or terse to control redundant lines of error reports.

Value range: default, verbose, and terse

\set ON_ERROR_STOP value

If this variable is set, the script execution stops immediately. If this script is invoked from another script, that script will be stopped immediately as well. If the outermost script is invoked using the -f option rather than from an interactive gsql session, gsql will return error code 3, indicating the difference between the current error and critical errors. (The error code for critical errors is 1.)

Value range: on/off, true/false, yes/no, and 1/0

\set AUTOCOMMIT [on|off]

Sets the auto commit behavior of the current gsql connection. on indicates that auto commit is enabled, and off indicates that auto commit is disabled. By default, the gsql connection is automatically committed, and each individual statement is implicitly committed. If auto commit is disabled for performance or other purposes, you need to explicitly run the COMMIT command to ensure that transactions are committed. For example, execute the COMMIT statement to explicitly commit transactions after a specified service SQL statement is executed. Particularly, ensure that all transactions are committed before the gsql client exits.

• on: The auto commit is enabled.
• off: The auto commit is disabled.

\set RETRY [retry_times]

Determines whether to enable the retry function if statement execution encounters errors. The parameter retry_times specifies the maximum number of retry times and the default value is 5. Its value ranges from 5 to 10. If the retry function has been enabled, when you run the \set RETRY command again, the retry function will be disabled.

The configuration file retry_errcodes.conf shows a list of errors. If these errors occur, retry is required. This configuration file is placed in the same directory as that for executable programs. This configuration file is configured by the system rather than by users and cannot be modified by the users.

The retry function can be used in the following error scenarios:

• YY002: TCP communication errors. Print information: Connection reset by peer. (reset between DNs)
• YY003: Lock timeout. Print information: Lock wait timeout.../wait transaction xxx sync time exceed xxx.
• YY004: TCP communication errors. Print information: Connection timed out.
• YY005: Failed to issue SET commands. Print information: ERROR SET query.
• YY006: Failed to apply for memory. Print information: memory is temporarily unavailable.
• YY007: Failed to allocate memory for the libcomm library. Print information: Memory allocate error.
• YY008: No data is received during libcomm communication. Print information: No data in buffer.
• YY009: A memory allocation error occurs during libcomm communication and the connection is closed. Print information: Close because releases memory.
• YY010: The control channel fails to send or receive data during libcomm communication. Print information: control channel is disconnect.
• YY011: The data channel fails to send or receive data during libcomm communication. Print information: data channel is disconnect.
• YY012: The peer connection is closed abnormally during libcomm communication. Print information: Stream closed by remote.
• YY013: Failed to receive data during libcomm communication. Print information: Wait poll unknown error.

If an error occurs, gsql queries connection status of all DNs. If the connection status is abnormal, gsql sleeps for 1 minute and tries again. In this case, the retries in most of the primary/standby switchover scenarios are involved.

Value range of retry_times: 5 to 10

\lo_list

Displays a list of all GaussDB large objects stored in the database, along with the comments provided for them.