刚接触mybaties 需要执行批量更新。
具体需求是，前端给我一个list,将list中的内容根据id在数据库中跟新数据。
要更新的list实体类为：
public class SysParamEntity {
private int id;
private String pcode;
private String label;
private String pvalue;
private String remark;
private String creater;
private Date createdDate;
private String modifier;
private Date modifiedDate;
}
要根据id批量跟新pvalue，modifier，modifiedDate，mapper.xml文件如下
<update id="batchUpdate">
update direct_bank_sys_param
<trim prefix="set" suffixOverrides=",">
<trim prefix="pvalue =case" suffix="end,">
<foreach collection="list" item="i" index="index">
<if test="i.pvalue!=null">
when id=#{i.id} then #{i.pvalue}
</if>
</foreach>
</trim>
<trim prefix=" modified_date =case" suffix="end,">
<foreach collection="list" item="i" index="index">
<if test="i.modifiedDate!=null">
when id=#{i.id} then #{i.modifiedDate}
</if>
</foreach>
</trim>
<trim prefix=" modifier =case" suffix="end,">
<foreach collection="list" item="i" index="index">
<if test="i.modifier!=null">
when id=#{i.id} then #{i.modifier}
</if>
</foreach>
</trim>
</trim>
where
<foreach collection="list" separator="or" item="i" index="index">
id=#{i.id}
</foreach>
</update>