Oracle读写文件操作相信大家都不陌生，下面就为您介绍Oracle读写文件bfilename的实例，希望对您学习Oracle读写文件方面能有所帮助。

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>createorreplacedirectoryUTL_FILE_DIRas'/opt/oracle/utl_file'; 
Directorycreated.SQL>declare 
fhandleutl_file.file_type; 
begin 
fhandle:=utl_file.fopen('UTL_FILE_DIR','example.txt','w'); 
utl_file.put_line(fhandle,'eygletestwriteone'); 
utl_file.put_line(fhandle,'eygletestwritetwo'); 
utl_file.fclose(fhandle); 
end; 
/ 
PL/SQLproceduresuccessfullycompleted. 
SQL>! 
[oracle@jumper9.2.0]$more/opt/oracle/utl_file/example.txt 
eygletestwriteone 
eygletestwritetwo 
[oracle@jumper9.2.0]$

类似的我们可以通过utl_file来读取文件:

SQL>declare 
fhandleutl_file.file_type; 
fp_buffervarchar2(4000); 
begin 
fhandle:=utl_file.fopen('UTL_FILE_DIR','example.txt','R'); 
 
utl_file.get_line(fhandle,fp_buffer); 
dbms_output.put_line(fp_buffer); 
utl_file.get_line(fhandle,fp_buffer); 
dbms_output.put_line(fp_buffer); 
utl_file.fclose(fhandle); 
end; 
/ 
eygletestwriteone 
eygletestwritetwo 
PL/SQLproceduresuccessfullycompleted.

可以查询dba_directories查看所有directory.

SQL>select*fromdba_directories; 
OWNERDIRECTORY_NAMEDIRECTORY_PATH------------------------------------------------------------------------------------------ 
SYSUTL_FILE_DIR/opt/oracle/utl_file 
SYSBDUMP_DIR/opt/oracle/admin/conner/bdump 
SYSEXP_DIR/opt/oracle/utl_file

可以使用drop directory删除这些路径.

SQL>dropdirectoryexp_dir;DirectorydroppedSQL>select*fromdba_directories;OWNERDIRECTORY_NAMEDIRECTORY_PATH------------------------------------------------------------------------------------------SYSUTL_FILE_DIR/opt/oracle/utl_fileSYSBDUMP_DIR/opt/oracle/admin/conner/bdump 
 
createorreplacedirectoryUSER_DIRas'E:\PLSQL\310\'; 

DECLARE 
v_contentVARCHAR2(1800); 
v_bfileBFILE; 
amountINT; 
offsetINT:=1; 
 
BEGIN 
v_bfile:=bfilename('USER_DIR','test.TXT');--注意这里的User_dir对应上面已经创建好啦的目录 
amount:=DBMS_LOB.getlength(v_bfile); 
DBMS_LOB.OPEN(v_bfile); 
DBMS_LOB.READ(v_bfile,amount,offset,v_content); 
DBMS_LOB.close(v_bfile); 
DBMS_OUTPUT.PUT_LINE(v_content); 
END;