1、连接
SQL*Plus system/manager
2、显示当前连接用户
SQL> show user
3、查看系统拥有哪些用户
SQL> select * from all_users;
4、新建用户并授权
SQL> create user a identified by a;（默认建在SYSTEM表空间下）
SQL> grant connect,resource to a;
5、连接到新用户
SQL> conn a/a
6、查询当前用户下全部对象
SQL> select * from tab;
7、建立第一个表
SQL> create table a(a number);
8、查询表结构
SQL> desc a
9、插入新记录
SQL> insert into a values(1);
10、查询记录
SQL> select * from a;
11、更改记录
SQL> update a set a=2;
12、删除记录
SQL> delete from a;
13、回滚
SQL> roll;
SQL> rollback;
14、提交
SQL> commit;
用户授权:
GRANT ALTER ANY INDEX TO "user_id "
GRANT "dba " TO "user_id ";
ALTER USER "user_id " DEFAULT ROLE ALL
创建用户:
CREATE USER "user_id " PROFILE "DEFAULT " IDENTIFIED BY " DEFAULT TABLESPACE "USERS " TEMPORARY TABLESPACE "TEMP " ACCOUNT UNLOCK;
GRANT "CONNECT " TO "user_id ";
用户password设定:
ALTER USER "CMSDB " IDENTIFIED BY "pass_word "
表空间创建:
CREATE TABLESPACE "table_space " LOGGING DATAFILE 'C:ORACLEORADATAdbs able_space.ora' SIZE 5M
------------------------------------------------------------------------
1、查看当前全部对象
SQL > select * from tab;
2、建一个和a表结构一样的空表
SQL > create table b as select * from a where 1=2;
SQL > create table b(b1,b2,b3) as select a1,a2,a3 from a where 1=2;
3、察看数据库的大小。和空间使用情况
SQL > col tablespace format a20
SQL > select b.file_id 文件ID,
b.tablespace_name 表空间,
b.file_name 物理文件名称,
b.bytes 总字节数,
(b.bytes-sum(nvl(a.bytes,0))) 已使用,
sum(nvl(a.bytes,0)) 剩余,
sum(nvl(a.bytes,0))/(b.bytes)*100 剩余百分比
from dba_free_space a,dba_data_files b
where a.file_id=b.file_id
group by b.tablespace_name,b.file_name,b.file_id,b.bytes
order by b.tablespace_name
/
dba_free_space --表空间剩余空间状况
dba_data_files --数据文件空间占用情况
4、查看现有回滚段及其状态
SQL > col segment format a30
SQL > SELECT SEGMENT_NAME,OWNER,TABLESPACE_NAME,SEGMENT_ID,FILE_ID,STATUS FROM DBA_ROLLBACK_SEGS;
5、查看数据文件放置的路径
SQL > col file_name format a50
SQL > select tablespace_name,file_id,bytes/1024/1024,file_name from dba_data_files order by file_id;
6、显示当前连接用户
SQL > show user
7、把SQL*Plus当计算器
SQL > select 100*20 from dual;
8、连接字符串
SQL > select
SQL > select concat(列1,列2)
from
9、查询当前日期
SQL > select to_char(sysdate,'yyyy-mm-dd,hh24:mi:ss') from dual;
10、用户间复制数据
SQL > copy from user1 to user2 create table2 using select * from table1;
11、视图中不能使用order by，但可用group by取代来达到排序目的
SQL > create view a as select b1,b2 from b group by b1,b2;
12、通过授权的方式来创建用户
SQL > grant connect,resource to test identified by test;
SQL > conn test/test
13、查出当前用户全部表名。
select unique tname from col;
-----------------------------------------------------------------------
alter table alist_table add address varchar2(100);
alter table alist_table modify address varchar2(80);
create table alist_table_copy as select ID,NAME,PHONE,EMAIL,
QQ as QQ2,
ADDRESS from alist_table;
drop table alist_table;
rename alist_table_copy to alist_table
空值处理
有时要求列值不能为空
create table dept (deptno number(2) not null, dname char(14), loc char(13));
在基表中添加一列
alter table dept
add (headcnt number(3));
改动已有列属性
alter table dept
modify dname char(20);
注：仅仅有当某列全部值都为空时。才干减小其列值宽度。
仅仅有当某列全部值都为空时，才干改变其列值类型。
仅仅有当某列全部值都为不空时，才干定义该列为not null。
例：
alter table dept modify (loc char(12));
alter table dept modify loc char(12);
alter table dept modify (dname char(13),loc char(12));
查找未断连接
select process,osuser,username,machine,logon_time ,sql_text
from v$session a,v$sqltext b where a.sql_address=b.address;
-----------------------------------------------------------------
1.以USER_開始的数据字典视图包括当前用户所拥有的信息,
select * from user_tables;
2.以ALL_開始的数据字典视图包括ORACLE用户所拥有的信息,
查询用户拥有或有权訪问的全部表信息:
select * from all_tables;
3.以DBA_開始的视图一般仅仅有ORACLE数据库管理员能够訪问:
select * from dba_tables;
4.查询ORACLE用户：
conn sys/change_on_install
select * from dba_users;
conn system/manager;
select * from all_users;
5.创建数据库用户：
CREATE USER user_name IDENTIFIED BY password;
GRANT CONNECT TO user_name;
GRANT RESOURCE TO user_name;
授权的格式: grant (权限) on tablename to username;
删除用户(或表):
drop user(table) username(tablename) (cascade);
6.向建好的用户导入数据表
IMP SYSTEM/MANAGER FROMUSER = FUSER_NAME TOUSER = USER_NAME FILE = C:EXPDAT.DMP COMMIT = Y
7.索引
create index [index_name] on [table_name]( "column_name ")