mysql
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添加索引
# 添加唯一索引 alter table t_device_record add UNIQUE uq_fieldid(file_id)
mybatis
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批量插入
<insert id="insertBatch" parameterType="java.util.List" useGeneratedKeys="true" keyProperty="id"> insert into t_device_record (id, title, user_id) values <foreach collection="datas" item="item" index="index" separator="," > ( #{item.id,jdbcType=BIGINT}, #{item.title,jdbcType=VARCHAR}, #{item.userId,jdbcType=BIGINT} ) </foreach> </insert>
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in 查询
<select id="getByFileIds" parameterType="java.util.List" resultMap="BaseResultMap"> select <include refid="Base_Column_List" /> from t_device_record where file_id in ( <foreach collection="fileIds" item="fileId" index="index" separator="," > #{fileId} </foreach> ) </select>
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批量插入或修改 (on duplicate key)
<insert id="insertBatch" parameterType="java.util.List" useGeneratedKeys="true" keyProperty="id"> insert into t_device_record (id, title, user_id) values <foreach collection="datas" item="item" index="index" separator="," > ( #{item.id,jdbcType=BIGINT}, #{item.title,jdbcType=VARCHAR}, #{item.userId,jdbcType=BIGINT} ) </foreach> on duplicate key update id = VALUES(id), title = VALUES(title) </insert>
java
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stream流获取list中某属性集合
//获取属性列表 List<Long> fileIds = items.stream().map(FeedbackAnalyzeItemOutVo::getFileId).collect(Collectors.toList()); //获取属性列表