CREATE TABLE vehicles ( vehicle_id INTEGER PRIMARY KEY, vin_number CHAR(17), last_checkup TIMESTAMP ); CREATE TABLE location ( time TIMESTAMP NOT NULL, vehicle_id INTEGER REFERENCES vehicles (vehicle_id), latitude FLOAT, longitude FLOAT ); SELECT create_hypertable('location', by_range('time...
public.by_range ('time', INTERVAL '7 days'), migrate_data => TRUE ); Step 4: Create hourly real time aggregate CREATE MATERIALIZED VIEW "SensorReadingsHourly" WITH ( timescaledb.continuous, timescaledb.materialized_only = FALSE ) AS SELECT public.time_bucket ('1 hour', "time") AS "t...
1. TimescaleDB是基于PostgreSQL的时序数据库插件,完全继承了PostgreSQL的功能,对于复杂查询,各种类型(GIS,json,k-v,图像特征值,range,数组,复合类型,自定义类型,...)的支持非常丰富,非常适合工业化的时序数据库场景需求。 1.1 支持丰富的数据类型,数组、范围类型、JSON类型、K-V类型、GIS类型、图类型等。满足更多...
4. 查询最近异常的数据 # Metrics about resource-constrained devicesSELECTtime, cpu, freemem, batteryFROMdevopsWHEREdevice_id='foo'ANDcpu>0.7ANDfreemem<0.2ORDERBYtimeDESCLIMIT100; 5. 计算最近7天,每小时的异常次数 # Calculate total errorsbylatest firmware versions #perhouroverthelast7daysSELECTdate_t...
1. TimescaleDB是基于PostgreSQL的时序数据库插件,完全继承了PostgreSQL的功能,对于复杂查询,各种类型(GIS,json,k-v,图像特征值,range,数组,复合类型,自定义类型,...)的支持非常丰富,非常适合工业化的时序数据库场景需求。 1.1 支持丰富的数据类型,数组、范围类型、JSON类型、K-V类型、GIS类型、图类型等。满足更多...
a regular SQL table CREATE TABLE conditions ( time TIMESTAMPTZ NOT NULL, location TEXT NOT NULL, temperature DOUBLE PRECISION NULL, humidity DOUBLE PRECISION NULL ); -- Convert the table into a hypertable that is partitioned by time SELECT create_hypertable('conditions', by_range('time')); ...
select('drop materialized view '|| user_view_name ||';')::varcharfrom_timescaledb_catalog.continuous_aggorderbysplit_part(user_view_name,'_',2), bucket_widthdesc; 查询最早和最晚数据时间 selectto_timestamp(min(range_start_integer) /1000)asmin, to_timestamp(max(range_end_integer) /...
涉及基于时间的 GROUP BY 的较大查询(在面向时间的分析中很常见)通常在 TimescaleDB 中实现卓越的性能。 例如,以下涉及 33M 行的查询在 TimescaleDB 中当整个(超)表为 100M 行时快 5 倍,而当它为 1B 行时快约2倍。 SELECT date_trunc('hour', time) as hour, ...
EXISTS timescaledb;--Create a regular SQL tableCREATETABLEconditions(timeTIMESTAMPTZNOT NULL, locationTEXTNOT NULL, temperatureDOUBLE PRECISIONNULL, humidityDOUBLE PRECISIONNULL);--Convert the table into a hypertable that is partitioned by timeSELECTcreate_hypertable('conditions', by_range('time'));...
single partial for each time range, and finalized into the value the user receives. In other words, to compute the average temperature, each partial sum is added up to the total sum, each partial count is added up to a total count, then the average is computed by total sum / total ...