code: function (joinType, table, tableAlias) {
              this.__joinType = joinType;
              this.__table = table;
              this.__tableAlias = tableAlias || null;
          }
docs: @lends patio.sql.JoinClause.prototype 
  Represents an SQL JOIN clause, used for joining tables.
  Created by {@link patio.Dataset} join methods.
  @constructs
  @augments patio.sql.Expression
  
  @param {String} joinType the type of join this JoinClause should use
  @param table the table to join with
  @param tableAlias the alias to use for this join clause
  
  @property {String} joinType <b>READ ONLY</b> the type of join this JoinClause should use
  @property table <b>READ ONLY</b> the table to join with
  @property joinType <b>READ ONLY</b> the alias to use for this join clause