在Oracle中从十六进制编码的CLOB转换为BLOB

时间:2017-02-02 12:54:18

标签: oracle plsql blob binary-data

我有一些存储在CLOB中的十六进制形式的大型二进制内容,并希望将其转换为BLOB,其中十六进制代码是实际的二进制字节编码:

DECLARE

  -- This would be my 8 byte hex-encoded binary content. Real content is much bigger
  c CLOB := 'cafebabe12345678';
  b BLOB;
BEGIN

  -- Need the implementation of this function
  b := hex_to_blob(c);
END;
/

使用PL / SQL在Oracle中最简单的方法是什么?

1 个答案:

答案 0 :(得分:3)

所需的功能可能如下所示:

CREATE OR REPLACE
FUNCTION hex_to_blob (hex CLOB) RETURN BLOB IS
  b BLOB                := NULL;
  s VARCHAR2(4000 CHAR) := NULL;
  l NUMBER              := 4000;
BEGIN
  IF hex IS NOT NULL THEN
    dbms_lob.createtemporary(b, FALSE);

    FOR i IN 0 .. LENGTH(hex) / 4000 LOOP
      dbms_lob.read(hex, l, i * 4000 + 1, s);
      dbms_lob.append(b, to_blob(hextoraw(s)));
    END LOOP;
  END IF;

  RETURN b;
END hex_to_blob;