检查文件是否存在？

Question

尝试检查我要读取的文件是否存在。

Answer 1

这是另一种方法：

1. 包装的用途BFILE和fileexists功能dbms_lob：

   create or replace function FileExists(
   

   p_DirName in varchar2, – schema object name
   p_FileName in varchar2
   ) return number
   is
   l_file_loc bfile;
   begin
   l_file_loc := bfilename(upper(p_DirName), p_FileName);
   return dbms_lob.fileexists(l_file_loc); – 1 exists; 0 - not exists
   end;
   
   
   

2. 包使用fgetattr功能utl_file：

   create or replace function FileExists(
   

   p_DirName in varchar2, – schema object name
   p_FileName in varchar2
   ) return number
   is
   l_fexists boolean;
   l_flen number;
   l_bsize number;
   l_res number(1);
   begin
   l_res := 0;
   utl_file.fgetattr(upper(p_DirName), p_FileName, l_fexists, l_flen, l_bsize);
   if l_fexists
   then
   l_res := 1;
   end if;
   return l_res;
   end;