Trying to read the file using utl_file method - sql

Question

I am trying to see if this file exists. But I'm getting this error message. I have already checked the privileges I got them. But this file is on the server side so is there something I am missing
DECLARE
vInHandle utl_file.file_type;
BEGIN
vInHandle := utl_file.fopen('IMG_UTL_DIR', 'image-file.csv', 'R');
IF utl_file.is_open(vInHandle) THEN
dbms_output.put_line('The File exists');
Else
dbms_output.put_line('The File not exists');
END IF;
END fopen;
Errors:
ORA-29283: invalid file operation
ORA-06512: at "SYS.UTL_FILE", line 536
ORA-29283: invalid file operation
ORA-06512: at line 5

Answer 1

If the file does not exist then you will get that error. With your code, when the file exists you will get:
anonymous block completed
The File exists
But when the file does not exist you will get:
Error report -
ORA-29283: invalid file operation
ORA-06512: at "SYS.UTL_FILE", line 536
ORA-29283: invalid file operation
ORA-06512: at line 6
29283. 00000 - "invalid file operation"
*Cause: An attempt was made to read from a file or directory that does
not exist, or file or directory access was denied by the
operating system.
*Action: Verify file and directory access privileges on the file system,
and if reading, verify that the file exists.
Note the 'a file or directory that does not exist' part of the error description. You cannot test for the file's existence like this. As far as I'm aware there is no direct way to test for a file being there; you would have to attempt to open the file and catch the exception. For example:
DECLARE
vInHandle utl_file.file_type;
eNoFile exception;
PRAGMA exception_init(eNoFile, -29283);
BEGIN
BEGIN
vInHandle := utl_file.fopen('IMG_UTL_DIR', 'image-file.csv', 'R');
dbms_output.put_line('The File exists');
EXCEPTION
WHEN eNoFile THEN
dbms_output.put_line('The File not exists');
END;
END fopen;
/
anonymous block completed
The File not exists
But the ORA-29283 exception can mean other things as well, as the description says, so it doesn't necessarily mean the file is not there - it could be there but not accessible for some other (permission-related) reason. You would also be masking the location of the actual error to some extent, and if you had multiple file operations in the block then you'd either have to wrap each one in its own begin/exception/end sub-block to specify the error, or lose the actual error point.
You're probably better off just letting the exception be raised and reported naturally, rather than catching it and replacing it with a dbms_output message which might not be retrieved and displayed by the client anyway.