function Write(const Buffer; Count: Integer): Integer
Use Write to write Count bytes to the BLOB or CLOB column, starting at the current position.
All the other data-writing methods of a TEWBBlobStream object (WriteBuffer, WriteComponent) call Write to do their actual writing.
Do not call Write when the TEWBBlobStream object was created in bmRead mode. Also, please remember that if you are using a stream on a CLOB column, then the number of characters in the CLOB column will not be equal to the number of bytes in the stream.