mybatis设置全局变量

1.在mybatis-config.xml中配置全局变量（

注意顺序，properties是第一个写在configuration中的标签：(properties?,settings?,typeAliases?,typeHandlers?,objectFactory?,objectWrapperFactory?,reflectorFactory?,plugins?,environments?,databaseIdProvider?,mappers?)）

2.在Mapper中使用全局变量

	
	
		SELECT
			god.goods_id AS 'goodsId',
			god.goods_name AS 'goodsName',
			CONCAT('${filePathPrefix}',god.goods_img_url) AS 'imgUrl',
			god.goods_price AS 'goodsPrice',
			god.market_price AS 'marketPrice',
			god.goods_num AS 'goodsNum'
		FROM
			gy_order_dtl god
		WHERE
			god.order_id = #{orderId}