oracle管理

随着数据的爆炸，表再所难免用到分区，再分区…
再搞一把partiton table

1，只读表空间可不可以后来创建表
2，只读表空间里先创建的表能不能删除
3，read only 是不是只禁用dml?
…

同一实例下，不同用户之间的数据同步导入
1，exp from a user,imp to b user,
2,impdp network_link,不生成dump文件直接导入
…

For a table to be recoverable using Flashback Drop, it must reside in a locally managed tablespace. Also, tables in the SYSTEM tablespaces cannot recovered using Flashback Drop regardless of the tablespace type.

Transportable tablespace feature introduced since Oracle 10g allowed a tablespace placed in a read only mode to be transported to another database and plugged in. However system and sysaux tablespaces were not transportable

In earlier releases of Oracle Database, the MAXTRANS parameter limited the number of transaction entries that could concurrently use data in a data block. This parameter has been deprecated.

system@ORCL> create table testnull(id int not null,name varchar2(10) not null);

Table created.

oracle 10 允许 基于表中某一列单独授权 update 权限

anbob@ORCL> conn system
Enter password:

重命名表名、字段名、索引名、约束名

SQL> CREATE TABLE test1 (
2 col1 NUMBER(10) NOT NULL,
3 col2 VARCHAR2(50) NOT NULL);
…….

Whether you are create table or alter table plus a filling, the column is asequence of before and after,In oracle you can modify the sequence.

for example: