加入购物车扣除库存逻辑修改

src/main/resources/mapper/TbProductMapper.xml

@@ -913,6 +913,12 @@
       where id = #{id,jdbcType=INTEGER}
   </update>
 
+  <update id="updateStockById">
+        update tb_product
+        set stock_number = stock_number - #{number,jdbcType=INTEGER}
+        where id = #{productId}
+  </update>
+
   <select id="selectByIdIn" resultMap="BaseResultMap">
     select *
     from tb_product