thanks for all replies!
It seems that there's no way that convert ROW type to CHARACTER directly.I've solved the problem indirectly.here is the way:
1.convert the ROW type to BLOB using ASBITSTREAM. ...
Currently i've tried using CAST(ROW AS CHARACTER),but it doesn't work;
I searched the manual and i found the CAST function doesn't support the ROW type.
I just tried using ASBITSTREAM to convert a X ...
i'm doing this in an easy way:
if you're using ORACLE database,create a storedproc called md5,so you can just use the sql "select md5(?) from dual" and passthru the sql you need with a para ...