http://blog.sina.com.cn/s/blog_713978a50100prkt.html
CLOB里存的是2進制
判定長度 ? DBMS_LOB.GETLENGTH(col1)
獲取文本 ? DBMS_LOB.SUBSTR(col1,n,pos)
DBMS_LOB.SUBSTR(col1,10,1)表示從第1個字節開始取出10個字節
DBMS_LOB.SUBSTR(CLOB_VAR,32767)表示截取CLOB變量保存的全部數據
DBMS_LOB.FILECLOSE(IMG_BFILE)關閉文件
?
clob轉化為字符串，SELECT ?UTL_RAW.CAST_TO_VARCHAR2(DBMS_LOB.SUBSTR(col1,10,1))? FROM ? tab1;
如果clob中包含空格則不能使用。
將clob類型轉化成字符串
create??or??replace??function?? getclob(
?????????table_name????????????in?? varchar2,
?????????field_id??????????????in?? varchar2,
?????????field_name????????????in?? varchar2,
?????????v_id??????????????????in?? number,
?????????v_pos?????????????????in??number)??return?? varchar2
is
?????????lobloc????????????????clob;
?????????buffer????????????????varchar2(32767);
?????????amount????????????????number??:=?? 2000;
?????????offset????????????????number??:=?? 1;
)
)
)
)
