时间：2021-08-29 08:57:54 | 栏目：JAVA代码 | 点击：次
1. 当查询的参数只有一个时
findByIds(List<Long> ids)
1.1 如果参数的类型是List, 则在使用时，collection属性要必须指定为 list
Xml代码
<select id="findByIdsMap" resultMap="BaseResultMap">
Select
<include refid="Base_Column_List" />
from jria where ID in
<foreach item="item" index="index" collection="list" open="(" separator="," close=")">
#{item}
</foreach>
</select>
<select id="findByIdsMap" resultMap="BaseResultMap">
Select
<include refid="Base_Column_List" />
from jria where ID in
<foreach item="item" index="index" collection="list" open="(" separator="," close=")">
#{item}
</foreach>
</select>
findByIds(Long[] ids)
1.2 如果参数的类型是Array,则在使用时，collection属性要必须指定为 array
Xml代码
<select id="findByIdsMap" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from tabs where ID in
<foreach item="item" index="index" collection="array" open="(" separator="," close=")">
#{item}
</foreach>
</select>
<select id="findByIdsMap" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from tabs where ID in
<foreach item="item" index="index" collection="array" open="(" separator="," close=")">
#{item}
</foreach>
</select>
2. 当查询的参数有多个时,例如 findByIds(String name, Long[] ids)
这种情况需要特别注意，在传参数时，一定要改用Map方式, 这样在collection属性可以指定名称
下面是一个示例
Map<String, Object> params = new HashMap<String, Object>(2);
params.put("name", name);
params.put("ids", ids);
mapper.findByIdsMap(params);
Xml代码
<select id="findByIdsMap" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from tabs where ID in
<foreach item="item" index="index" collection="ids" open="(" separator="," close=")">
#{item}
</foreach>
</select>
总结