influxdb删除某一列数据（某一个数据点的历史数据）操作

[Zhang书书]

删除某一列 （重要：看完下面说明，一定要看实际例子）

一个表有3个field（数据点），想去掉field3

1、除了field3列的数据都转移到临时"表"tmp上 (time,id,department是三个必填的tag)：
select tag1, tag2, field1, field2 into tmp from old_measurement group by * ;

2、删除旧"表"中的数据：drop measurement old_measurement;

3、数据转移到旧"表"：select tag1, tag2, field1, field2 into old_measurement from tmp group by * ;

4、删除临时"表"：drop measurement tmp;

实际例子：(id字段特殊，所以写法不同)

SELECT "time", "id"::STRING, "aa", "bb" into "tmp" from "abc123" group by * ;

drop measurement "abc123";

SELECT "time", "id"::STRING, "aa", "bb" into "abc123" from "tmp" group by * ;

drop measurement tmp;

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如果删除某时间范围内的

删除前14天的话，在第一步查询时限定查询范围
SELECT "time", "id"::STRING, "aa", "bb" into "tmp" from "abc123" WHERE time > now() - 14d group by * ;