达梦DM 8数据库之数据库表操作
1、创建表的SQL表语句如下:
CREATE TABLE "DMHR"."CITY"
(
"CITY_ID" CHAR(3) NOT NULL,
"CITY_NAME" VARCHAR(40),
"REGION_ID" INT,
CONSTRAINT "CITY_C_ID_PK" NOT CLUSTER PRIMARY KEY("CITY_ID"),
CONSTRAINT "CITY_REG_FK" FOREIGN KEY("REGION_ID") REFERENCES "DMHR"."REGION"("REGION_ID")
)
STORAGE(ON "MAIN", CLUSTERBTR) ;
COMMENT ON COLUMN "DMHR"."CITY"."CITY_NAME" IS '城市名称';
2、表字段注释,SQL代码如下:
COMMENT ON column DMHR.CITY.CITY_NAME IS '城市名称';
3、插入数据,SQL代码如下:
INSERT INTO DMHR.CITY(CITY_ID,CITY_NAME,REGION_ID) VALUES('LA','六安',2);
4、查看表的表空间、所属者等信息,SQL代码如下:
select * from dba_tables where table_name = 'CITY';
5、查询创建的表结构,SQL代码如下:
select dbms_metadata.get_ddl('TABLE','CITY','DMHR');
sp_tabledef('DMHR','CITY');
6、重命名表,SQL代码如下:
alter table DMHR.CITY rename to CITY2;
7、--增加列
alter table DMHR.CITY add BZ varchar(18);
--删除列
alter table DMHR.CITY drop BZ;
8、--表注释
COMMENT ON TABLE DMHR.CITY IS '城市';
9、--删除表
drop table DMHR.CITY;
10、--查看表的约束信息;
select * from dba_constraints where table_name='CITY';