docs: def build_view_from_tag(self, tag):
          """
          Build a view of group of Symbols based on their tag.
          
          Parameters
          ----------
          tag : str
              Use '%' to enable SQL's "LIKE" functionality.
          
          Note
          ----
          
          This function is written without SQLAlchemy,
          so it only tested on Postgres.
  
          """
          
          syms = self.search_tag(tag)
          
          names = [sym.name for sym in syms]
          
          subs = ["SELECT indx, '{}' AS symbol, final FROM {}".format(s, s) for s in names]
          
          qry = " UNION ALL ".join(subs)
          
          qry = "CREATE VIEW {} AS {};".format(tag, qry)
  
          self.ses.execute("DROP VIEW IF EXISTS {};".format(tag))
          self.ses.commit()        
          self.ses.execute(qry)
          self.ses.commit()