package com.youkeda.comment.dao;
import com.youkeda.comment.dataobject.UserDO;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import java.time.LocalDateTime;
import java.util.List;
//fhadmin.cn
@Mapper
public interface UserDAO {
int batchAdd(@Param("list") List<UserDO> userDOs);
}
<insert id="batchAdd" parameterType="java.util.List" useGeneratedKeys="true" keyProperty="id">
INSERT INTO user (user_name, pwd, nick_name,avatar,gmt_created,gmt_modified)
VALUES
<foreach collection="list" item="it" index="index" separator =",">
(#{it.userName}, #{it.pwd}, #{it.nickName}, #{it.avatar},now(),now())
</foreach >
</insert>
foreach相當於執行力java的for循環,他的屬性:
collection指定集合的上下文參數名稱比如這裏的@Param("list")
item指定遍歷的每一個數據的變量,一般叫it,可以使用it.userName來獲取具體的值
index集合的索引值,從0開始
separator遍歷每條記錄並添加分隔符
除了批量插入,使用SQL in查詢多個用戶時也會使用:
package com.youkeda.comment.dao;
import com.youkeda.comment.dataobject.UserDO;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import java.time.LocalDateTime;
import java.util.List;
//fhadmin.cn
@Mapper
public interface UserDAO {
List<UserDO> findByIds(@Param("ids") List<Long> ids);
}
<select id="findByIds" resultMap="userResultMap">
select * from user
<where>
id in
<foreach item="item" index="index" collection="ids"
open="(" separator="," close=")">
#{item}
</foreach>
</where>
</select>
- open
- close
select * from user where id in (?,?,?)