今天遇到一个问题 之前用timescaledb创建的超表 是已7天为单位的 由于7天的数据量过大 影响查询效率 需要把7天的分区改为一天一分区
创建超表 create_hypertable()
1.创建普通版表
1
2
3
4
5
6
7
|
create table "超表名" ( "collect_time" timestamp (6) not null , "code" varchar (36) collate "pg_catalog" . "default" not null , "value" numeric (14,4) not null , "create_time" timestamp (6) not null ) ; |
2.改为超表 create_hypertable()
1
|
select create_hypertable( '超表名' , 'collect_time' , chunk_time_interval => interval '7 day' ); |
3.插入数据
1
2
3
4
5
|
insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2020-10-15 16:35:00' , '22255220522' , '23.4672' , '2020-10-14 16:35:26.659' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2020-10-16 16:35:00' , '26622569666' , '0.1085' , '2020-10-14 16:35:27.546' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2020-10-13 16:35:00' , '525941155555' , '25.0549' , '2020-10-14 16:35:28.473' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2020-10-14 16:35:00' , '744445411114' , '0.0000' , '2020-10-14 16:35:24.01' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2020-10-12 16:35:00' , '774484457444' , '0.0000' , '2020-10-14 16:35:23.032' ); |
查看分区,你会发现这些数据在2个分区内
修改分区 set_chunk_time_interval()
一.查看分区情况
1.查看_timescaledb_catalog.dimension 表
1
|
select * from "_timescaledb_catalog" . "dimension" |
interval_length上显示 604800000000 (timestamp类型)意思是一周
2.查看分区块状态
查看 dimension_slice 表
转换时间戳
1602720000000000 2020-10-15 08:00:00
1603324800000000 2020-10-22 08:00:00
这里可以看到分区是7天的
二.修改分区时间 set_chunk_time_interval()
1.修改分区时间
1
|
select set_chunk_time_interval( '超表名' , interval '24 hours' ); |
2.插入数据验证
1
2
3
4
5
6
|
insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2021-1-14 16:35:00' , '375222d001' , '27.7932' , '2020-10-14 16:35:15.011' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2021-1-15 16:35:00' , '3715044111' , '0.0000' , '2020-10-14 16:35:20.389' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2021-1-16 16:35:00' , '202q0019qt001' , '0.3663' , '2020-10-14 16:35:19.087' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2021-1-17 16:35:00' , '3702000284441' , '22.2946' , '2020-10-14 16:35:15.035' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2021-1-18 16:35:00' , '37075225555501' , '0.3022' , '2020-10-14 16:35:24.041' ); insert into 超表名( "collect_time" , "code" , "value" , "create_time" ) values ( '2021-1-19 16:35:00' , '25555222206001' , '0.0000' , '2020-10-14 16:35:23.956' ); |
三.查看 修改结果
查看_timescaledb_catalog.dimension 表
变成 86400000000 了
2.查看分区
分区也多了
还有第2种(未测试)
我想能不能直接"_timescaledb_catalog".“dimension” 表的 interval_length 字段直接 改为86400000000
到此这篇关于postgresql 数据库 timescaledb 修改分区时间(范围)的文章就介绍到这了,更多相关postgresql 数据库 timescaledb 分区时间内容请搜索服务器之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持服务器之家!
原文链接:https://blog.csdn.net/yang_z_1/article/details/112766944