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1 kingbase服务
1.1 查看kingbase数据库服务进程
ps -ef|grep kingbase
1.2 命令启动kingbase数据库服务
# /opt/Kingbase/ES/V8 为金仓安装目录
# /opt/Kingbase/ES/V8/data 为金仓数据目录
# sys_ctl是数据库服务器启停命令，通过-D选项来来指定数据库数据目录
# 注意要切换成kingbase用户
/opt/Kingbase/ES/V8/Server/bin/sys_ctl -D /opt/Kingbase/ES/V8/data start
1.3 命令停止kingbase数据库服务
# /opt/Kingbase/ES/V8 为金仓安装目录
# /opt/Kingbase/ES/V8/data 为金仓数据目录
# sys_ctl是数据库服务器启停命令，通过-D选项来来指定数据库数据目录
# 注意要切换成kingbase用户
/opt/Kingbase/ES/V8/Server/bin/sys_ctl -D /opt/Kingbase/ES/V8/data stop
1.4 命令重启kingbase数据库服务
# /opt/Kingbase/ES/V8 为金仓安装目录
# /opt/Kingbase/ES/V8/data 为金仓数据目录
# sys_ctl是数据库服务器启停命令，通过-D选项来来指定数据库数据目录
# 注意要切换成kingbase用户
/opt/Kingbase/ES/V8/Server/bin/sys_ctl -D /opt/Kingbase/ES/V8/data restart
1.5 查询licence有效期
select GET_LICENSE_VALIDDAYS();
1.6 修改字符编码
alter table 模式名称.表名称 CHARACTER SET utf8 COLLATE utf8_general_ci
1.7 查看语言
select * from sys_language
1.8 查看角色用户
select * from sys_user
1.9 查看会话进程
select * from sys_stat_activity
1.10 查看当前账号会话数
select count(*), usename from sys_stat_activity group by usename
1.11 查看系统所有表
SELECT * FROM sys_tables
1.12 查看表字段
select * from information_schema.columns
1.13 查看索引
select * from sys_index
2 数据库操作
2.1 查看所有数据库
select * from sys_database
2.2 查看表空间
select * from sys_tablespace
2.3 查看数据库大小
# 查看kingbase数据库的大小，单位字节
select sys_database_size('kingbase')
# 查看kingbase数据库的大小，格式化后单位兆
select sys_size_pretty(sys_database_size('kingbase'));
2.4 查看所有数据库大小
select sys_database.datname, sys_database_size(sys_database.datname) as size from sys_database order by size desc;
2.5 查看数据库模式大小
SELECT sys_size_pretty(sum(table_size)::bigint) as "disk space",sum(table_size)::bigint as "total size"
FROM (SELECT sys_catalog.sys_namespace.nspname as schema_name,sys_total_relation_size(sys_catalog.sys_class.oid) as table_sizeFROM sys_catalog.sys_class JOIN sys_catalog.sys_namespace ON relnamespace = sys_catalog.sys_namespace.oidWHERE sys_catalog.sys_namespace.nspname = 'kingbase'
) t
2.6 查看数据库所有模式大小
SELECT schema_name, sys_size_pretty(sum(table_size)::bigint) as "disk space",sum(table_size)::bigint as "total size"
FROM (SELECT sys_catalog.sys_namespace.nspname as schema_name,sys_total_relation_size(sys_catalog.sys_class.oid) as table_sizeFROM sys_catalog.sys_class JOIN sys_catalog.sys_namespace ON relnamespace = sys_catalog.sys_namespace.oidWHERE sys_catalog.sys_namespace.nspname NOT IN ('information_schema','src_restrict','anon','dbms_sql','xlog_record_read','pg_catalog','pg_bitmapindex','sys_catalog','sysaudit','sysmac','sys')
) t
GROUP BY schema_name
2.7 查看单表大小
select sys_size_pretty(sys_relation_size('kingbase.test_szie'));
2.8 查询模式下所有表大小
SELECT
table_name,
sys_size_pretty(table_size) AS table_size,
sys_size_pretty(indexes_size) AS indexes_size,
sys_size_pretty(total_size) AS total_size
FROM (
SELECT
table_name,
sys_table_size(table_name) AS table_size,
sys_indexes_size(table_name) AS indexes_size,
sys_total_relation_size(table_name) AS total_size
FROM (
SELECT ('"' || table_schema || '"."' || table_name || '"') AS table_name
FROM information_schema.TABLES WHERE table_schema ='kingbase'
) AS all_tables
ORDER BY total_size DESC
) AS pretty_sizes
2.9 查询数据库连接情况
select * from pg_stat_activity
2.10 杀死空闲连接
SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE state='idle'
2.11 查询最大连接数
show max_connections
2.12 查询超级连接数
show superuser_reserved_connections
2.13 查看大小写情况
# V8R3查看,ON-敏感,OFF-不敏感
show case_sensitive
# V8R6查看,ON-不敏感,OFF-敏感
show enable_ci
2.14 查询客户端、服务端编码
show server_encoding;
show client_encoding;
2.15 设置客户端、服务端编码
set client_encoding to 'GBK';
set server_encoding to 'UTF-8';
3 模式操作
3.1 模式创建
CREATE SCHEMA 模式名称
3.2 模式删除
DROP SCHEMA 模式名称
3.3 修改模式名称
alter schema 被修改模式名称 rename to 需要重命名模式名称
3.4 查询数据库下所有模式名称
SELECT DISTINCT TABLE_SCHEMA FROM INFORMATION_SCHEMA.TABLES;
3.5 查询数据库下所有模式数量
SELECT COUNT(DISTINCT TABLE_SCHEMA) FROM INFORMATION_SCHEMA.TABLES;
3.6 查询指定模式下表名称
SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE' AND TABLE_SCHEMA='PUBLIC';
3.7 查询指定模式下指定表字段类型、注释等信息
SELECT '表名称' AS table_name, col.COLUMN_NAME,CASE WHEN col.UDT_NAME='VARCHAR' THEN CONCAT(col.UDT_NAME,'(',col.character_maximum_length,')') ELSE col.UDT_NAME END AS UDTNAME,d.DESCRIPTION FROM information_schema.COLUMNS colJOIN SYS_CLASS c ON c.RELNAME = col.TABLE_NAMELEFT JOIN SYS_DESCRIPTION d ON d.OBJOID = c.OID AND d.OBJSUBID = col.ORDINAL_POSITIONLEFT JOIN sys_constraint s on c.OID = s.conrelid and col.ORDINAL_POSITION=ANY(conkey::int[])WHERE col.table_schema = '模式名称'AND col.TABLE_NAME = '表名称';
4 表操作
4.1 创建表
CREATE TABLE "sub_test"."t_table"(
id VARCHAR(32) NOT NULL，
remark VARCHAR(255),
length INT8,
front TEXT,
status TINYINT,
range FLOAT8,
create_time TIMESTAMP,
image_info JSON,
info JSON,
result JSON,
CONSTRAINT "t_table_PKEY" PRIMARY KEY ("id")
);
CREATE INDEX "createTime" ON "sub_test".t_table(create_time);
comment on column weather.remark is '备注';
comment on column weather.length is '长度';
comment on column weather.status is '状态';
comment on column weather.range is '范围';
comment on column weather.create_time is '创建时间';
4.2 创表–自增字段和主键
id设置为主键，同时类型指定为serial，创建之后，id即为自增。
CREATE TABLE "sub_test"."t_table"( id SERIAL NOT NULL,host_name VARCHAR(125),port VARCHAR(32),type TINYINT,launch_date TIMESTAMP,modify_time TIMESTAMP,create_time TIMESTAMP,CONSTRAINT "t_table_PKEY" PRIMARY KEY ("id")
);
4.3 将字段改为自增
# 将字段改为自增
ALTER TABLE sub_test."t_table" ALTER column id set default nextval('sub_test.t_table_id_SEQ');
# 删除约束（主键就是一个约束）
ALTER TABLE sub_test."t_table" DROP CONSTRAINT t_table_constraint_1;# 添加主键
ALTER TABLE sub_test."t_table" ADD PRIMARY KEY(id);
4.4 修改字段类型
# 语法
alter table 模式名称.表名称 modify 修改字段 需要被修改字段类型
# 示例
alter table sub_test.tb_filegroup modify bbox varchar(32)
4.5 修改字段名称
# 语法
alter table 模式名称.表名称 rename 字段 to 修改字段
# 示例
alter table sub_test.tb_filegroup rename "bbox" to "b_box"
alter table sub_test.tb_filegroup rename COLUMN bbox to b_box
4.6 修改字段为 ----非空
# 语法
alter table 模式名称.表名称 alter 字段 set not null
# 示例
alter table sub_test.tb_filegroup alter data_level set not null;
4.7 修改非空字段为 ----空
# 语法
alter table 模式名称.表名称 alter 字段 drop not null
# 示例
示例：
alter table sub_test.tb_filegroup alter data_level drop not null;
4.8 添加字段
# 语法
alter table 模式名称.表名称 add 添加字段 字段类型
# 示例
alter table sub_test.tb_filegroup add COLUMN bbox varchar(255) default '10';
4.9 删除字段
# 语法
alter table 模式名称.表名称 drop 需要删除字段
# 示例
alter table sub_test.tb_filegroup drop bbox
4.10 添加字段注释
# 语法
comment on column 表名称.字段名称 is ‘注释内容’
# 示例
comment on column sub_test.tb_filegroup.bbox is '方位'
4.11 创建索引
# 语法
CREATE INDEX "索引名称" ON 模式名称.表名称 (字段名称)
# 示例
CREATE INDEX "metadataGroupId" ON "sub_test".tb_filegroup(metadataId);
5 创建数据库模式用户授权一体化操作
# 创建用户MYTEST
create user MYTEST password '123456';
# 创建MYTEST数据库
create database MYTEST;
# 赋予MYTEST用户操作数据库权限
GRANT connect on database MYTEST to MYTEST;
grant all privileges on all tables in schema public to MYTEST;
grant all privileges on all sequences in schema public to MYTEST;
grant all privileges on database MYTEST to MYTEST;
grant all privileges on schema public to MYTEST with grant option;
# 创建schema并指定用户MYTEST
CREATE SCHEMA IF NOT EXISTS MYTEST;
ALTER SCHEMA MYTEST OWNER TO MYTEST;
COMMENT ON SCHEMA MYTEST IS 'standard MYTEST schema';