How to save big data in Oracle to CLOB

If the data is too large, we cannot directly assign values to the clob variable. In this case, we can use the dbms_lob.read and dbms_lob.write methods to read and write clob variables in stages. However, we should set up a cache for the clob variable. The first sentence is as follows. Here is an example program. You can change the order of dbms_lob.read and dbms_lob.write so that the program can not only write big data but also read big data.

Dbms_lob.createtemporary (lob_loc => x_clob,
Cache => TRUE );
PROCEDURE load_clob (p_clob_in CLOB,
X_clob in out nocopy clob) IS

L_clob_len NUMBER: = dbms_lob.getlength (p_clob_in );
Rochelle data VARCHAR2 (32756 );
Rochelle buf_len_std NUMBER: = 4000;
Rochelle buf_len_cur NUMBER;
Rochelle seg_count NUMBER;
Rochelle write_offset NUMBER;
BEGIN
IF p_clob_in IS NOT NULL THEN
Rochelle seg_count: = floor (l_clob_len/Rochelle buf_len_std );
FOR I IN 0 .. l_seg_count
LOOP

IF I = l_seg_count THEN
Rochelle buf_len_cur: = l_clob_len-I * Rochelle buf_len_std;
ELSE
Rochelle buf_len_cur: = l_buf_len_std;
End if;

IF l_buf_len_cur> 0 THEN
Dbms_lob.read (lob_loc => p_clob_in,
Amount => l_buf_len_cur,
Offset => I * l_buf_len_std + 1,
Buffer => l_data );
Rochelle write_offset: = nvl (dbms_lob.getlength (lob_loc => x_clob ),
0) + 1;
Dbms_lob.write (lob_loc => x_clob,
Amount => l_buf_len_cur,
Offset => l_write_offset,
Buffer => l_data );
End if;
End loop;
End if;
END load_clob;