PLSQL changing XML file content

Question

Hello Experts,
I have a task to do.
I have to replace special characters from an XML file placed on the server through PLSQL.
So that i created a plsql procedure.
PROCEDURE REMOVE_SPECIAL_CHARS (p_file_name IN VARCHAR2)
AS
l_tmp_clob       CLOB                             DEFAULT EMPTY_CLOB();
l_bfile          BFILE NULL;
l_dest_offset    INTEGER            := 1;
l_src_offset     INTEGER            := 1;
l_outfile        UTL_FILE.file_type;
lang_ctx         NUMBER             := DBMS_LOB.default_lang_ctx;
warning          NUMBER NULL;
l_dest_file      VARCHAR2(300) NULL;
BEGIN
mob_util_pck.log_write ('I','Inside REMOVE_SPECIAL_CHARS procedure(+)');
l_dest_file:=SUBSTR (p_file_name, (INSTR (p_file_name, '/', -1, 1))+1);
mob_util_pck.log_write ('I','Following File will be modified: '||l_dest_file);  
   l_bfile := BFILENAME ('MOBSEPAOUT', l_dest_file);
   DBMS_LOB.OPEN (l_bfile, DBMS_LOB.file_readonly);
   DBMS_LOB.createtemporary (l_tmp_clob, TRUE);
   DBMS_LOB.loadclobfromfile (dest_lob          => l_tmp_clob
                            , src_bfile         => l_bfile
                            , amount            => DBMS_LOB.getlength (l_bfile)
                            , dest_offset       => l_dest_offset
                            , src_offset        => l_src_offset
                            , bfile_csid        => DBMS_LOB.default_csid
                            , lang_context      => lang_ctx
                            , warning           => warning
   DBMS_LOB.CLOSE (l_bfile);
mob_util_pck.log_write ('I','Deleting Old File');
   BEGIN
      mob_util_pck.delete_files ('MOBSEPAOUT'
                               , l_dest_file
   END;
mob_util_pck.log_write ('I','Before Replacing Characters');
   l_tmp_clob := REPLACE (l_tmp_clob, '€', 'E');
   l_tmp_clob := REPLACE (l_tmp_clob, '@', '(at)');
   l_tmp_clob := REPLACE (l_tmp_clob, '&', '+');
   l_tmp_clob := REPLACE (l_tmp_clob, 'à', 'a');
   l_tmp_clob := REPLACE (l_tmp_clob, 'é', 'e');
   l_tmp_clob := REPLACE (l_tmp_clob, 'è', 'e');
   l_tmp_clob := REPLACE (l_tmp_clob, 'ç', 'c');
   l_tmp_clob := REPLACE (l_tmp_clob, 'ù', 'u');
   l_tmp_clob := REPLACE (l_tmp_clob, 'ï', 'i');
   l_tmp_clob := REPLACE (l_tmp_clob, 'ù', 'u');
   l_tmp_clob := REPLACE (l_tmp_clob, '[', '(');
   l_tmp_clob := REPLACE (l_tmp_clob, ']', ')');
   l_tmp_clob := REPLACE (l_tmp_clob, '\', '/');
   l_tmp_clob := REPLACE (l_tmp_clob, '^', '.');
   l_tmp_clob := REPLACE (l_tmp_clob, 'ù', 'u');
   --l_tmp_clob := REPLACE (l_tmp_clob, '_', '-');
   l_tmp_clob := REPLACE (l_tmp_clob, '`', '''');
   l_tmp_clob := REPLACE (l_tmp_clob, '{', '(');
   l_tmp_clob := REPLACE (l_tmp_clob, '|', '/');
   l_tmp_clob := REPLACE (l_tmp_clob, '}', ')');
   l_tmp_clob := REPLACE (l_tmp_clob, '~', '-');
   l_tmp_clob := REPLACE (l_tmp_clob, 'À', 'A');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Á', 'A');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Â', 'A');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ã', 'A');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ä', 'A');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Å', 'A');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ç', 'C');
   l_tmp_clob := REPLACE (l_tmp_clob, 'È', 'E');
   l_tmp_clob := REPLACE (l_tmp_clob, 'É', 'E');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ê', 'E');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ë', 'E');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ì', 'I');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Í', 'I');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Î', 'I');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ï', 'I');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ñ', 'N');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ò', 'O');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ó', 'O');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ô', 'O');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Õ', 'O');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ö', 'O');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ù', 'U');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ú', 'U');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Û', 'U');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ü', 'U');
   l_tmp_clob := REPLACE (l_tmp_clob, 'Ý', 'Y');
   mob_util_pck.log_write ('I','After Replacing Special Characters');
   mob_util_pck.log_write ('I','Before Creating New File '||l_dest_file);
   DBMS_XSLPROCESSOR.clob2file(l_tmp_clob, 'MOBSEPAOUT', l_dest_file);
   mob_util_pck.log_write ('I','After Creating New File '||l_dest_file);
   mob_util_pck.log_write ('I','Inside REMOVE_SPECIAL_CHARS procedure(-)');
END REMOVE_SPECIAL_CHARS;
This procedure is working fine for some special characters. But some special characters are getting replaced by different characters before performing the replace so it is causing wrong replacement of characters.
eg- i need to replace & by +
but it is changing it to +amp which is incorrect.
Is it something related to characters encoding?
Please help.
Regards-
Vikrant

Answer 1

eg- i need to replace & by +
but it is changing it to +amp which is incorrect.
Is it something related to characters encoding?
Due to its special meaning in the XML language, occurrences of the ampersand character '&' have be escaped to &amp; as well as '<', '>' and '"' respectively to &lt;, &gt; and &quot;.
So in short, do not replace the ampersand character.