docs: def add_sql(self, value, clause):
          """
          Add a WHERE clause to the state.
  
          :param value:
              The unknown to bind into the state. Uses SQLBuilder._map_value() to map this into an appropriate database
              compatible type.
          :param clause:
              A SQL fragment defining the restriction on the unknown value
          """
          if value is not None:
              self.sql_args.append(SQLBuilder.map_value(value))
              self.where_clauses.append(clause)