华为openGauss高斯数据库 - gsql用法_业界新闻

发布时间:2024-07-13 20:15

阅读量:2

1.3.11 \d TableName命令

1.3.12 \di IndexName命令

1.3.18 \! os_command命令

1.3.19 \o fileName命令

1.3.20 \i file.sql命令

1.3.21 \conninfo命令

1.3.22 \c[onnect] [DBNAME]命令

1.3.23 \echo [string]命令

1.3.24 \q命令和快捷键ctrl+d

1.1 gsql的语法

gsql --help

[omm@test ~]$ gsql --help

gsql is the FusionInsight LibrA interactive terminal.

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

-l, --list list available databases, then exit

-v, --set=, --variable=NAME=VALUE

set gsql variable NAME to VALUE

-V, --version output version information, then exit

-X, --no-gsqlrc do not read startup file (~/.gsqlrc)

-1 ("one"), --single-transaction

execute command file as a single transaction

-?, --help show this help, then exit

Input and output options:

-a, --echo-all echo all input from script

-e, --echo-queries echo commands sent to server

-E, --echo-hidden display queries that internal commands generate

-k, --with-key=KEY the key for decrypting the encrypted file

-L, --log-file=FILENAME send session log to file

-m, --maintenance can connect to cluster during 2-pc transaction recovery

-n, --no-libedit disable enhanced command line editing (libedit)

-o, --output=FILENAME send query results to file (or |pipe)

-q, --quiet run quietly (no messages, only query output)

-s, --single-step single-step mode (confirm each query)

-S, --single-line single-line mode (end of line terminates SQL command)

Output format options:

-A, --no-align unaligned table output mode

-F, --field-separator=STRING

set field separator (default: "|")

-H, --html HTML table output mode

-P, --pset=VAR[=ARG] set printing option VAR to ARG (see \pset command)

-R, --record-separator=STRING

set record separator (default: newline)

-r if this parameter is set,use libedit

-t, --tuples-only print rows only

-T, --table-attr=TEXT set HTML table tag attributes (e.g., width, border)

-x, --expanded turn on expanded table output

-z, --field-separator-zero

set field separator to zero byte

-0, --record-separator-zero

set record separator to zero byte

Connection options:

-h, --host=HOSTNAME database server host or socket directory (default: "/opt/gaussdbi/tmp")

-p, --port=PORT database server port (default: "5432")

-U, --username=USERNAME database user name (default: "omm")

-W, --password=PASSWORD the password of specified database user

For more information, type "\?" (for internal commands) or "\help" (for SQL

commands) from within gsql, or consult the gsql section in the FusionInsight LibrA

documentation.

Report bugs to <pgsql-bugs@postgresql.org>.

[omm@test ~]$

1.2 gsql常用选项

1.2.1 最常用的必要选项

使用gsql命令，用数据库用户student，连接到openGauss数据库管理系统下的studentdb数据库：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=>

其中的选项说明如下：

-d选项：指定gsql客户端连接的数据库

-h选项：指定gsql客户端连接的服务器IP

-U选项：指定gsql客户端连接数据库的用户名

-p选项：指定gsql客户端连接的服务器端口号

-W选项：指定gsql客户端连接的用户密码

1.2.2 -r选项

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r

gsql命令的-r选项，第一个作用是当我们在gsql中执行了很多语句后，如果我们想重新执行之前执行过的语句，可以使用上箭头和下箭头，向前和向后翻阅之前执行过的命令和SQL语句。

执行下面的语句：使用上箭头可以提供很多便利性。

SELECT * FROM instructor WHERE salary=90000;

studentdb=> SELECT * FROM instructor WHERE salary=90000;

id | dept_name | name | salary

----------+------------------+---------+----------

12121 | Finance | Wu | 90000.00

(1 row)

studentdb=>

1.2.3 -E选项

-E选项会让gsql客户端程序再执行元命令的时候，显示其对应的SQL语句。

使用Linux用户omm，打开一个Linux终端窗口，执行gsql的元命令\l，该命令的作用是显示当前系统有哪些数据库：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -E

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -E

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=> \l

********* QUERY ********** -E选项会显示gsql客户端的元命令对应的SQL语句

SELECT d.datname as "Name",

pg_catalog.pg_get_userbyid(d.datdba) as "Owner",

pg_catalog.pg_encoding_to_char(d.encoding) as "Encoding",

d.datcollate as "Collate",

d.datctype as "Ctype",

pg_catalog.array_to_string(d.datacl, E'\n') AS "Access privileges"

FROM pg_catalog.pg_database d

ORDER BY 1;

**************************

List of databases

-----------+-------+-----------+---------+-------+-------------------

postgres | omm | SQL_ASCII | C | C |

studentdb | omm | SQL_ASCII | C | C |

template0 | omm | SQL_ASCII | C | C | =c/omm +

template1 | omm | SQL_ASCII | C | C | =c/omm +

(4 rows)

studentdb=> \q

[omm@test ~]$

如果不使用-E选项，同样执行上面的命令系列，结果如下：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=> \l

List of databases

-----------+-------+-----------+---------+-------+-------------------

postgres | omm | SQL_ASCII | C | C |

studentdb | omm | SQL_ASCII | C | C |

template0 | omm | SQL_ASCII | C | C | =c/omm +

template1 | omm | SQL_ASCII | C | C | =c/omm +

(4 rows)

studentdb=> \q

[omm@test ~]$

可以看出，如果没有-E选项，不会显示元命令\l对应的SQL查询语句。

1.2.4 -t选项

-t选项会让gsql客户端程序在执行SQL查询语句的时候，返回的结果不显示列名及返回结果的行数。

使用Linux用户omm，打开一个Linux终端窗口，执行如下的命令：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -t

select * from instructor where salary=80000;

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -t

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=> select * from instructor where salary=80000;

76543 | Finance | Singh | 80000.00

98345 | Elec. Eng. | Kim | 80000.00

studentdb=> \q

[omm@test ~]$

1.2.5 -A选项

-A选项会让gsql客户端程序在执行SQL查询语句的时候，不对齐显示查询返回的行数据,如图6-7所示（列不是对齐的！）。

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -A

select * from instructor where salary=80000;

图6-8 -A选项表示不对齐显式

可以将-A和-t两个选项同时应用，表示不对齐显示，也不显示列名和返回行数：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -At

select * from instructor where salary=80000;

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r -At

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=> select * from instructor where salary=80000;

76543|Finance|Singh|80000.00

98345|Elec. Eng.|Kim|80000.00

studentdb=> \q

[omm@test ~]$

1.2.6 -v选项

-v选项会让gsql客户端程序在命令行中设置gsql环境变量。

如果我们想在命令行中告诉gsql启动后关闭自动提交，设置为手动事务提交，可以执行如下命令：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-v AUTOCOMMIT=off -r

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -v AUTOCOMMIT=off -r

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=>

1.2.7 -c选项

-c选项会让gsql客户端程序直接在命令行中运行SQL语句，示例如下：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-c "select * from instructor where salary=80000"

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -c "select * from instructor where salary=80000"

id | dept_name | name | salary

----------+--------------------+------------+----------

76543 | Finance | Singh | 80000.00

98345 | Elec. Eng. | Kim | 80000.00

(2 rows)

[omm@test ~]$

1.2.8 -f选项

-f选项会让gsql客户端程序直接在命令行中直接运行SQL脚本文件。

首先用omm用户，生成一个测试用的SQL语句脚本：

cat > test.sql<<EOF

select * from instructor where salary=80000;

EOF

[omm@test ~]$ cat > test.sql<<EOF

> select * from instructor where salary=80000;

> EOF

[omm@test ~]$

然后使用gsql客户端程序在命令行中直接执行刚刚创建的SQL语句脚本：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -f test.sql

rm test.sql

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -f test.sql

id | dept_name | name | salary

-------+------------+-------+----------

76543 | Finance | Singh | 80000.00

98345 | Elec. Eng. | Kim | 80000.00

(2 rows)

total time: 0 ms

[omm@test ~]$ rm test.sql

[omm@test ~]$

1.2.9 -q选项

-q选项会让gsql客户端程序以安静的方式运行，只显示查询结果。

首先用omm用户，执行下面的gsql命令（使用了-q选项），创建test表，然后再次执行gsql命令（不使用-q选项），删除刚刚创建的test表，接着再次执行gsql命令（不使用-q选项），重新创建test表，最后又一次执行gsql命令（使用了-q选项），删除刚刚创建的test表：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-c "create table test(col char)" -q

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-c "drop table test"

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-c "create table test(col char)"

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-c "drop table test" -q

[omm@test script]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -c "create table test(col char)" -q

[omm@test script]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -c "drop table test"

DROP TABLE

[omm@test script]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -c "create table test(col char)"

CREATE TABLE

[omm@test script]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -c "drop table test" -q

[omm@test script]$

我们发现使用了-q选项的gsql没有显示任何信息。

执行下面的命令，进行SQL查询，我们发现虽然有-q选项，但是会显示查询结果。

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

-c "select * from instructor where salary=80000" -q

[omm@test script]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 \

> -c "select * from instructor where salary=80000" -q

id | dept_name | name | salary

----------+---------------------+----------+----------

76543 | Finance | Singh | 80000.00

98345 | Elec. Eng. | Kim | 80000.00

(2 rows)

[omm@test script]$

1.3 gsql的元命令

本节的测试均使用下面的命令登录到openGauss数据库：

gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r

[omm@test ~]$ gsql -d studentdb -h 192.168.100.91 -U student -p 26000 -W student@ustb2020 -r

gsql ((openGauss 1.0.1 build 13b34b53) compiled at 2020-10-12 02:00:59 commit 0 last mr )

SSL connection (cipher: DHE-RSA-AES128-GCM-SHA256, bits: 128)

Type "help" for help.

studentdb=>

1.3.1 \l命令

元命令\l的作用是显示openGauss数据库集簇中，目前有哪些数据库：

studentdb=> \l

List of databases

-----------+-------+-----------+---------+-------+-------------------

postgres | omm | SQL_ASCII | C | C |

studentdb | omm | SQL_ASCII | C | C |

template0 | omm | SQL_ASCII | C | C | =c/omm +

template1 | omm | SQL_ASCII | C | C | =c/omm +

(4 rows)

studentdb=>

1.3.2 \du命令和\dg命令

元命令\dg命令与元命令\du命令的作用类似，都是显示openGauss数据库集簇中，目前有哪些用户和角色。

\du

\dg

studentdb=> \du

List of roles

Role name | Attributes | Member of

-----------+------------------------------------------------------------------------+-----------

omm | Sysadmin, Create role, Create DB, Replication, Administer audit, UseFT | {}

student | Sysadmin | {}

studentdb=> \dg

List of roles

Role name | Attributes | Member of

-----------+------------------------------------------------------------------------+-----------

omm | Sysadmin, Create role, Create DB, Replication, Administer audit, UseFT | {}

student | Sysadmin | {}

studentdb=>

1.3.3 \db命令

元命令\db的作用是显示openGauss数据库集簇中，目前有哪些表空间：

\db

studentdb=> \db

List of tablespaces

Name | Owner | Location

---------------------+-----------+------------------------

pg_default | omm |

pg_global | omm |

student_ts | omm | tablespace/student_ts1

(3 rows)

studentdb=>

1.3.4 \dn命令

元命令\dn的作用是显示当前数据库，有哪些数据库模式：

\dn

studentdb=> \dn

List of schemas

Name | Owner

--------------+------------

cstore | omm

dbe_perf | omm

public | omm

snapshot | omm

(4 rows)

studentdb=>

1.3.5 \d命令

元命令\d的作用是显示当前数据库下的所有的数据库对象(相当于命令\dtvsE，这里E表示外部表)：

List of relations

Schema | Name | Type | Owner | Storage

-----------+---------------------+----------+----------------+----------------------------------

public | advisor | table | student | {orientation=row,compression=no}

public | classroom | table | student | {orientation=row,compression=no}

public | course | table | student | {orientation=row,compression=no}

public | department | table | student | {orientation=row,compression=no}

public | instructor | table | student | {orientation=row,compression=no}

public | prereq | table | student | {orientation=row,compression=no}

public | section | table | student | {orientation=row,compression=no}

public | student | table | student | {orientation=row,compression=no}

public | takes | table | student | {orientation=row,compression=no}

public | teaches | table | student | {orientation=row,compression=no}

public | time_slot | table | student | {orientation=row,compression=no}

(11 rows)

studentdb=>

1.3.6 \dt命令

元命令\dt的作用是显示数据库中所有的表：

\dt

studentdb=> \dt

List of relations

Schema | Name | Type | Owner | Storage

--------+------------+-------+---------+----------------------------------