ORACLE directory 目录

Create directory让我们可以在Oracle数据库中灵活的对文件进行读写操作，极大的提高了Oracle的易用性和可扩展性。

其语法为:

CREATE [OR REPLACE] DIRECTORY directory AS 'pathname';

 

本案例具体创建如下:

 

            create or replace directory exp_dir as '/tmp';

 

目录创建以后，就可以把读写权限授予特定用户，具体语法如下:

GRANT READ[,WRITE] ON DIRECTORY directory TO username;

 

例如:

 

            grant read, write on directory exp_dir to eygle;

 

此时用户eygle就拥有了对该目录的读写权限。

 

 

让我们看一个简单的测试:

 

            SQL> create or replace directory UTL_FILE_DIR as '/opt/oracle/utl_file';

            Directory created.

            SQL> declare

            2    fhandle utl_file.file_type;

            3  begin

            4    fhandle := utl_file.fopen('UTL_FILE_DIR', 'example.txt', 'w');

            5    utl_file.put_line(fhandle , 'eygle test write one');

            6    utl_file.put_line(fhandle , 'eygle test write two');

            7    utl_file.fclose(fhandle);

            8  end;

            9  /

            PL/SQL procedure successfully completed.

            SQL> !

            [oracle@jumper 9.2.0]$ more /opt/oracle/utl_file/example.txt

            eygle test write one

            eygle test write two

            [oracle@jumper 9.2.0]$

 

类似的我们可以通过utl_file来读取文件:

            SQL> declare

            2    fhandle   utl_file.file_type;

            3    fp_buffer varchar2(4000);

            4  begin

            5    fhandle := utl_file.fopen ('UTL_FILE_DIR','example.txt', 'R');

            6

            7    utl_file.get_line (fhandle , fp_buffer );

            8    dbms_output.put_line(fp_buffer );

            9    utl_file.get_line (fhandle , fp_buffer );

            10    dbms_output.put_line(fp_buffer );

            11    utl_file.fclose(fhandle);

            12  end;

            13  /

            eygle test write one

            eygle test write two

            PL/SQL procedure successfully completed.

 

可以查询dba_directories查看所有directory.

 

            SQL> select * from dba_directories;

            OWNER                         DIRECTORY_NAME                 DIRECTORY_PATH

            ------------------------------ ------------------------------ ------------------------------

            SYS                                 UTL_FILE_DIR                 /opt/oracle/utl_file

            SYS                                 BDUMP_DIR                   /opt/oracle/admin/conner/bdump

            SYS                                 EXP_DIR                         /opt/oracle/utl_file

 

可以使用drop directory删除这些路径. 

            SQL> drop directory exp_dir;

            Directory dropped

            SQL> select * from dba_directories;

            OWNER                          DIRECTORY_NAME                 DIRECTORY_PATH

            ------------------------------ ------------------------------ ------------------------------

            SYS                                 UTL_FILE_DIR                 /opt/oracle/utl_file

            SYS                                 BDUMP_DIR                    /opt/oracle/admin/conner/bdump