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  • Oracle Directory

    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

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  • 原文地址:https://www.cnblogs.com/datalife/p/1985324.html
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