DBMS_LOB을 이용한 BLOB 데이타 HANDLING 예제 프로그램

Question

제품 : PRECOMPILERS
작성날짜 : 1998-09-15
DBMS_LOB을 이용한 BLOB 데이타 HANDLING 예제 프로그램
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1) select 하는 예제
- pro*c 2.2에서 compile하는 경우는 package로 DBMS_LOB package 호출을
encapsulate 해서 사용해야 하고, proc 8.0 이상에서 compile하는 경우
DBMS_LOB package를 직접 호출하는 것이 가능하다.
- make 방법
PRO*C 8.0인 경우
$ make -f demo_proc.mk EXE=my_prog OBJS=my_prog.o build \
PROCFLAGS="sqlcheck=full userid=scott/tiger define=V8"
PRO*C 2.2:
$ setenv TWO_TASK v8_alias
$ make -f proc.mk EXE=my_prog OBJS=my_prog.o build \
PROCFLAGS="sqlcheck=full userid=scott/tiger"
- 수행 SQL Script
create or replace package blob_it as
my_blob blob;
function get_blob_len return number;
procedure read_blob(amount in out number, offset in number,
buf in out raw);
end;
create or replace package body blob_it as
function get_blob_len return number is
begin
return DBMS_LOB.GETLENGTH(my_blob);
end;
procedure read_blob(amount in out number, offset in number,
buf in out raw) is
begin
DBMS_LOB.READ(my_blob,amount,offset,buf);
end;
end;
drop table lob_tab;
create table lob_tab (c1 number, c2 blob);
insert into lob_tab values (1,
utl_raw.cast_to_raw('AAAAAAAaaaaaaaaaa'));
- Program 예제
#include <stdio.h>
#include <string.h>
#define TERM(X) ( X.arr[X.len] = '\0' )
#define SLEN(X) ( X.len = strlen((char *)X.arr) )
#define READ_SIZE 60
EXEC SQL INCLUDE SQLCA;
/* Structure for VARRAW */
typedef struct {short len; char arr[READ_SIZE];} vr;
EXEC SQL BEGIN DECLARE SECTION;
VARCHAR oracleid[20];
EXEC SQL TYPE vr IS VARRAW(READ_SIZE);
vr my_vr;
EXEC SQL END DECLARE SECTION;
FILE *fp;
main()
char action_str[30];
long amount;
long offset;
short done;
long total;
EXEC SQL WHENEVER SQLERROR DO o_error(action_str);
strcpy( (char *)oracleid.arr, "scott/tiger" );
SLEN( oracleid );
strcpy( action_str, "connecting to d/b" );
EXEC SQL CONNECT :oracleid;
fp = fopen("my_blob.dat","wb");
strcpy( action_str, "fetching blob locator" );
EXEC SQL EXECUTE
BEGIN
select c2 into blob_it.my_blob from lob_tab
where c1 = 1;
#ifndef V8
:total := blob_it.get_blob_len;
#else
:total := DBMS_LOB.GETLENGTH(blob_it.my_blob);
#endif
END;
END-EXEC;
amount = READ_SIZE;
offset = 1;
done = 0;
strcpy( action_str, "reading from blob" );
while (!done)
EXEC SQL EXECUTE
BEGIN
#ifndef V8
blob_it.read_blob(:amount,:offset,:my_vr);
#else
DBMS_LOB.READ(blob_it.my_blob,:amount,:offset,:my_vr);
#endif
END;
END-EXEC;
offset += amount;
if (offset >= total)
done = 1;
fwrite(my_vr.arr,(size_t)amount,(size_t)1,fp);
fclose(fp);
EXEC SQL WHENEVER SQLERROR CONTINUE;
EXEC SQL ROLLBACK WORK RELEASE;
int o_error( action_str )
char *action_str;
int i;
char error_str[150];
EXEC SQL WHENEVER SQLERROR CONTINUE;
for ( i = 0; i < sqlca.sqlerrm.sqlerrml; i++ )
error_str[i] = sqlca.sqlerrm.sqlerrmc;
error_str[i] = '\0';
printf( "\nFailed with following Oracle error while %s:\n\n%s",
action_str, error_str );
EXEC SQL ROLLBACK WORK RELEASE;
exit(1);
2) insert 하는 예제
- 수행 SQL문
create directory BFILE_DIR as '/mnt3/rctest80/ldt';
- make 방법
$ make -f demo_proc.mk EXE=my_prog OBJS=my_prog.o build \
PROCFLAGS="sqlcheck=full userid=scott/tiger"
- Bfile을 이용하여 데이타를 로드하는 프로그램 예제
#include <stdio.h>
#include <string.h>
#define SLEN(X) ( X.len = strlen((char *)X.arr) )
EXEC SQL INCLUDE SQLCA;
VARCHAR oracleid[20];
FILE *fp;
main()
char action_str[30];
EXEC SQL WHENEVER SQLERROR DO o_error(action_str);
strcpy( (char *)oracleid.arr, "scott/tiger" );
SLEN( oracleid );
strcpy( action_str, "connecting to d/b" );
EXEC SQL CONNECT :oracleid;
EXEC SQL EXECUTE
DECLARE
lobd BLOB;
fils BFILE :=BFILENAME('BFILE_DIR', 'a30.bmp');
amt INTEGER;
BEGIN
insert into lob_tab values (1, empty_blob())
returning c2 into lobd;
DBMS_LOB.FILEOPEN(fils, dbms_lob.file_readonly);
DBMS_LOB.LOADFROMFILE(lobd, fils, dbms_lob.getlength(fils));
DBMS_LOB.FILECLOSE(fils);
END;
END-EXEC;
EXEC SQL COMMIT WORK RELEASE;
int o_error( action_str )
char *action_str;
int i;
char error_str[150];
EXEC SQL WHENEVER SQLERROR CONTINUE;
for ( i = 0; i < sqlca.sqlerrm.sqlerrml; i++ )
error_str[i] = sqlca.sqlerrm.sqlerrmc[i];
error_str[i] = '\0';
printf( "\nFailed with following Oracle error while %s:\n\n%s",
action_str, error_str );
EXEC SQL ROLLBACK WORK RELEASE;
exit(1);

Answer 1