Re: Pro*C and Oracle 6 How to read Long type?

B.LAPA (etjr_at_ci.ua.pt) wrote:
> Hi,
 

> Can anyone tell me how to retrieve a LONG datatype using Pro*C?
> The data i'll read will be chars.
> Thanks for any help

If you know the max size and can afford a static memory allocation use a char array to retrieve the value. If not then you should probably have another column which holds the length of the long column.
so your table def should be
...
LNG_LEN NUMBER(x)
LNG_COL LONG
...

Then in PROC
long sql_lng_len;
char* sql_lng_col;

to use it
EXEC SQL

select ...., LNG_LEN, ..., rowid, ... /* not lng_col */
into   ...., :sql_lng_len,.,:sql_rowid, ...
from ...
where ...  ;

sql_lng_col = malloc ( sql_lng_len + 1 ); memset ( sql_lng_col, 'A', sql_lng_len ); sql_lng_col [sql_lng_col] = '\0'; /* because pro c uses strlen to

                                      see how much to fetch.  If you
                                      have a char array it would use 
                                      sizeof */

EXEC SQL
select LNG_COL
into :sql_lng_col
from ...
where rowid = :sql_rowid;

hope this helps.

--
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*                          Saad Ahmad                        *
*                          E-Mail: sahmad_at_mfa.com            *
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