Mybatis 大家想必用得很多，这里给大家介绍两个实战小经验
1 if 标签嵌套
<select> select xxx, ccc from A left join B on A.a = B.a <if test="param='value'"> left join C on C.c = A.c </if> where A.active = 1 <if test="param1 = 'value2'"> and (B.b = '111' <if test="param2 = 'value3'"> or C.x = #{aaa} </if> ) </if> </select>
2.list 可以使用 contains 判断是否包含某个值
注意， 假如list里面是字符串话要对引号进行转义
<select> select * from A where A.a = '' <if test="list.contains("3")"> and A.b = '' </if> </select>
