Using SQL*Loader and UTL_FILE to load and unload large files(i.e. PDF) [message #132197] |
Thu, 11 August 2005 05:38 |
rgoynka
Messages: 1 Registered: August 2005 Location: Pune
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Junior Member |
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Problem : Load PDF or similiar files( stored at operating system) into an oracle table using SQl*Loader .
and than Unload the files back from oracle tables to prevoius format.
I 've used SQL*LOADER .... " sqlldr " command as :
" sqlldr scott/tiger@OraServer.com control=c:\sqlldr\control.ctl log=c:\any.txt "
Control file is written as :
LOAD DATA
INFILE 'c:\sqlldr\r_sqlldr.txt'
REPLACE
INTO table r_sqlldr
Fields terminated by ','
(
id sequence (max,1) ,
fname char(20),
data LOBFILE(fname) terminated by EOF )
It loads files ( Pdf, Image and more...) that are mentioned in file r_sqlldr.txt into oracle table r_sqlldr
Text file ( used as source ) is written as :
c:\kalam.pdf,
c:\CTSlogo1.bmp
c:\any1.txt
after this load ....i used UTL_FILE to unload data and write procedure like ...
CREATE OR REPLACE PROCEDURE R_UTL AS
l_file UTL_FILE.FILE_TYPE;
l_buffer RAW(32767);
l_amount BINARY_INTEGER ;
l_pos INTEGER := 1;
l_blob BLOB;
l_blob_len INTEGER;
BEGIN
SELECT data
INTO l_blob
FROM r_sqlldr
where id= 1;
l_blob_len := DBMS_LOB.GETLENGTH(l_blob);
DBMS_OUTPUT.PUT_LINE('blob length : ' || l_blob_len);
IF (l_blob_len < 32767) THEN
l_amount :=l_blob_len;
ELSE
l_amount := 32767;
END IF;
DBMS_LOB.OPEN(l_blob, DBMS_LOB.LOB_READONLY);
l_file := UTL_FILE.FOPEN('DBDIR1','Kalam_out.pdf','w', 32767);
DBMS_OUTPUT.PUT_LINE('File opened');
WHILE l_pos < l_blob_len LOOP
DBMS_LOB.READ (l_blob, l_amount, l_pos, l_buffer);
DBMS_OUTPUT.PUT_LINE('Blob read');
l_pos := l_pos + l_amount;
UTL_FILE.PUT_RAW(l_file, l_buffer, TRUE);
DBMS_OUTPUT.PUT_LINE('writing to file');
UTL_FILE.FFLUSH(l_file);
UTL_FILE.NEW_LINE(l_file);
END LOOP;
UTL_FILE.FFLUSH(l_file);
UTL_FILE.FCLOSE(l_file);
DBMS_OUTPUT.PUT_LINE('File closed');
DBMS_LOB.CLOSE(l_blob);
EXCEPTION
WHEN OTHERS THEN
IF UTL_FILE.IS_OPEN(l_file) THEN
UTL_FILE.FCLOSE(l_file);
END IF;
DBMS_OUTPUT.PUT_LINE('Its working at last');
END R_UTL;
/
This loads data from r_sqlldr table (BOLBS) to files on operating system ,,,
-> Same procedure with minor changes is used to unload other similar files like Images and text files.
In above example : Loading : 3 files 1) Kalam.pdf 2) CTSlogo1.bmp 3) any1.txt are loaded into oracle table r_sqlldr 's 3 rows respectively.
file names into fname column and corresponding data into data ( BLOB) column.
Unload : And than these files are loaded back into their previous format to operating system using UTL_FILE feature of oracle.
so PROBLEM IS : Actual capacity (size ) of these files is getting unloaded back but with quality decreased. And PDF file doesnt even view its data. means size is almot equal to source file but data are lost when i open it.....
and for images .... imgaes are getting loaded an unloaded but with colors changed ....
Also features ( like FFLUSH ) of Oracle 've been used but it never worked
ANY SUGGESTIONS OR aLTERNATE SOLUTION TO LOAD AND UNLOAD PDFs through Oracle ARE REQUESTED.
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