Retrieves all or part of the CLOB value designated by this Clob object as a stream of characters.
|pos||The position of the first character in the CLOB value to be extracted.
The first character is at position 1.
|length||The number of consecutive characters to be copied.|
Returns a java.io.Reader object that contains up to length consecutive characters from the CLOB value designated by this Clob object, starting with the character at position pos.