Parameters
- ordinal
 - The zero-based column ordinal.
 - fieldOffset
 - The index within the field where the read operation is to begin.
 - buffer
 - The buffer into which to read the stream of bytes.
 - bufferOffset
 - The index where buffer is to begin the write operation.
 - length
 - The maximum length to copy into the buffer.
 
Return Value
The actual number of bytes read.