Description of the illustration lead.eps

LEAD
  { ( value_expr [, offset [, default]] ) [ { RESPECT | IGNORE } NULLS ] 
  | ( value_expr [ { RESPECT | IGNORE } NULLS ] [, offset [, default]] )
  }
  OVER 
  { window_name 
  | { [window_name] | [query_partition_clause] } order_by_clause 	     
}