Method copy_value

sql/field.cc:8921–8940

Copy a value from another BLOB field of the same character set. This method is used by Copy_field, e.g. during ALTER TABLE. */

  This method is used by Copy_field, e.g. during ALTER TABLE.
*/
int Field_blob::copy_value(Field_blob *from)
{
  DBUG_ASSERT(field_charset()->eq_collation(from->charset()));
  DBUG_ASSERT(!compression_method() == !from->compression_method());
  int rc= 0;
  uint32 length= from->get_length();
  uchar *data= from->get_ptr();
  if (packlength < from->packlength)
  {
    set_if_smaller(length, Field_blob::max_data_length());
    length= (uint32) Well_formed_prefix(field_charset(),
                                        (const char *) data, length).length();
    rc= report_if_important_data((const char *) data + length,
                                 (const char *) data + from->get_length(),
                                 true);
  }
  store_length(length);
  bmove(ptr + packlength, (uchar*) &data, sizeof(char*));
  return rc;
}


int Field_blob::store(const char *from,size_t length,CHARSET_INFO *cs)