正在看的ORACLE教程是: oracle常用sql语句。 1、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; 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 a20 SQL > 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 |