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、查询当前用户下所有对象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;
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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 ";用户密码设定:ALTER USER "CMSDB " IDENTIFIED BY "pass_word "表空间创建:CREATE TABLESPACE "table_space " LOGGING DATAFILE 'C:\ORACLE\ORADATA\dbs\table_space.ora' SIZE 5M
------------------------------------------------------------------------
1、查看当前所有对象
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 a20SQL > select b.file_id 文件ID, b.tablespace_name 表空间, b.file_name 物理文件名, 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 a30SQL > 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 a50SQL > 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 列1 | |列2 from 表1;SQL > select concat(列1,列2) from 表1;
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代替来达到排序目的
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、查出当前用户所有表名。
select unique tname from col;
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/* 向一个表格添加字段 */alter table alist_table add address varchar2(100);
/* 修改字段 属性 字段为空 */alter table alist_table modify address varchar2(80);
/* 修改字段名字 */create table alist_table_copy as select ID,NAME,PHONE,EMAIL,QQ as QQ2, /*qq 改为qq2*/ADDRESS from alist_table;
drop table alist_table;rename alist_table_copy to alist_table/* 修改表名 */
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));
在基表中增加一列alter table deptadd (headcnt number(3));
修改已有列属性alter table deptmodify dname char(20);注：只有当某列所有值都为空时，才能减小其列值宽度。只有当某列所有值都为空时，才能改变其列值类型。只有当某列所有值都为不空时，才能定义该列为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_textfrom v$session a,v$sqltext b where a.sql_address=b.address;
-----------------------------------------------------------------1.以USER_开始的数据字典视图包含当前用户所拥有的信息, 查询当前用户所拥有的表信息:select * from user_tables;2.以ALL_开始的数据字典视图包含ORACLE用户所拥有的信息,查询用户拥有或有权访问的所有表信息:select * from all_tables;
3.以DBA_开始的视图一般只有ORACLE数据库管理员可以访问:select * from dba_tables;
4.查询ORACLE用户：conn sys/change_on_installselect * 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 = Y7.索引create index [index_name] on [table_name]( "column_name ")intersect运算
返回查询结果中相同的部分
exp:各个部门中有哪些相同的工种
selectjob
fromaccount
intersect
selectjob
fromresearch
intersect
selectjob
fromsales;
minus运算
返回在第一个查询结果中与第二个查询结果不相同的那部分行记录。
有哪些工种在财会部中有，而在销售部中没有？
exp:selectjobfromaccount
minus
selectjobfromsales;
1. oracle安装完成后的初始口令?
internal/oracle
sys/change_on_install
system/manager
scott/tiger
sysman/oem_temp
2. oracle9ias web cache的初始默认用户和密码？
administrator/administrator
3. oracle 8.0.5怎么创建数据库?
用orainst。假如有motif界面，可以用orainst /m
4. oracle 8.1.7怎么创建数据库?
dbassist
5. oracle 9i 怎么创建数据库?
dbca
6. oracle中的裸设备指的是什么?
裸设备就是绕过文件系统直接访问的储存空间
7. oracle如何区分 64-bit/32bit 版本？？？
$ sqlplus '/ as sysdba'
sql*plus: release 9.0.1.0.0 - production on mon jul 14 17:01:09 2003
(c) copyright 2001 oracle corporation. all rights reserved.
connected to:
oracle9i enterprise edition release 9.0.1.0.0 - production
with the partitioning option
jserver release 9.0.1.0.0 - production
sql> select * from v$version;
banner
----------------------------------------------------------------
oracle9i enterprise edition release 9.0.1.0.0 - production
pl/sql release 9.0.1.0.0 - production
core 9.0.1.0.0 production
tns for solaris: version 9.0.1.0.0 - production
nlsrtl version 9.0.1.0.0 - production
sql>
8. svrmgr什么意思？
svrmgrl，server manager.
9i下没有，已经改为用sqlplus了
sqlplus /nolog
变为归档日志型的
9. 请问如何分辨某个用户是从哪台机器登陆oracle的?
select machine , terminal from v$session;
10. 用什么语句查询字段呢？
desc table_name 可以查询表的结构
select field_name,... from ... 可以查询字段的值
select * from all_tables where table_name like '%'
select * from all_tab_columns where table_name='??'
11. 怎样得到触发器、过程、函数的创建脚本？
desc user_source
user_triggers
12. 怎样计算一个表占用的空间的大小？
select owner,table_name,
num_rows,
blocks*aaa/1024/1024 "size m",
empty_blocks,
last_analyzed
from dba_tables
where table_name='xxx';
here: aaa is the value of db_block_size ;
xxx is the table name you want to check