Cumulusmx.db


Introduction

In CumulusMX version 3, this database contains the Recent History. The SqlCache and the sqlite_sequence tables are not for normal usage. It is an SQLite datebase only to be maintained by CumulusMX. When removed it will be rebuilt. The database is stored in the data directory so its relative path is data/cumulusmx.db (case dependent on Linux).

A good tool to inspect this database is DB Browser for SQLite (external site). Editing the default tables takes you to unsupported territory but it might be educational to inspect.

Note: The CumulusMX Weather Diary also uses a SQLite database stored in data/diary.db.

The Recent History Data Table

This table has the following columns:

Column number # Column name Column type Properties Description
0 Timestamp datetime Primary Key, can never be NULL, No Default Value, Dates and times for the last 7 days, at whatever interval available (at logging interval for historic archive data, at one minute intervals while MX is running)
1 WindSpeed float Not NULL, No Default Value The average wind speed (see Wind_measurement#Weather_Stations_and_Cumulus for links) calculated at the stated time, if necessary converted to units requested
2 WindGust float Not NULL, No Default Value The spot gust speed recorded at the stated time, if necessary converted to units requested
3 WindLatest float Not NULL, No Default Value The spot latest wind speed recorded at the stated time, if necessary converted to units requested
4 WindDir integer Not NULL, No Default Value The wind bearing (0 =calm), (1 to 360 = number of degrees)
5 WindAvgDir integer Not NULL, No Default Value The average wind bearing over the defined period
6 OutsideTemp float Not NULL, No Default Value The measured outside air temperature, if necessary converted to units requested
7 WindChill float Not NULL, No Default Value The wind chill, either calculated by MX, or supplied by weather station. (Note: strictly only valid for low temperatures and significant wind speeds)
8 DewPoint float Not NULL, No Default Value The dew point, either calculated by MX, or supplied by weather station, for the stated time.
9 HeatIndex float Not NULL, No Default Value The USA Heat index as calculated by Cumulus for the stated time (if the temperature is high enough)
10 Humidity float Not NULL, No Default Value The Relative Humidity reported by the station at the stated time
11 Pressure float Not NULL, No Default Value The sea level pressure at the stated time, either as reported by the station or calculated by Cumulus from the absolute pressure reported by the station, if necessary converted to units requested
12 RainToday float Not NULL, No Default Value The rainfall for today so far, calculated by Cumulus from the rain counter (column 15) now minus the rain counter at start of day, if necessary converted to units requested
13 SolarRad integer Not NULL, No Default Value Solar radiation value reported by station at stated time
14 UV float Not NULL, No Default Value The Ultra Violet Index reported by station at stated time
15 raincounter float Not NULL, No Default Value The rain counter is used by Cumulus for all rainfall outputs, this is its value at stated time
16 FeelsLike float Not NULL, No Default Value The Feels Like temperature calculated by MX at stated time
17 Humidex float Not NULL, No Default Value The Canadian Humidity Index, calculated by Cumulus at the stated time
18 AppTemp float Not NULL, No Default Value The Apparent temperature, calculated by MX at the stated time
19 IndoorTemp float Not NULL, No Default Value The indoor temperature directly as reported by station at stated time
20 IndoorHumidity integer (0 decimal places, contrast with column 10) Not NULL, No Default Value The indoor relative humidity directly as reported by station at stated time
21 SolarMax integer Not NULL, No Default Value The calculated maximum value for solar radiation at stated time
22 Pm2p5 float Not NULL, No Default Value Air Quality expressed in terms of particulate matter of 2.5 μm, or less, (?? Rolling 24 hours average ??)
23 Pm10 float Not NULL, No Default Value Air Quality expressed in terms of particulate matter of 10 μm, or less, (?? Rolling 24 hours average ??)
24 RainRate float Not NULL, No Default Value The rainfall rate calculated for the stated time

See Recent history page.

SqlCache table

This table is fully managed by CumulusMX. You are not supposed to edit contents, you can view to quench your curiosity.

There is a MX setting (Settings=>MySQL settings=>General Options=>tick Buffer commands on failure) that when enabled allows failed commands to be stored here. The buffer is lost when CumulusMX is restarted.

This table holds a list of MySQL commands that are in the queue for MySqlConnect to run again.

Commands that fail because the database server is down are added to the queue when the setting is enabled (although MX will not save more than one query referencing same primary key). Because the error returned by the server cannot be predetermined, MX instead checks the error returned is not one of the following reasons before adding it to queue:

  • ParseError (the query does not make sense)
  • EmptyQuery (query has not been specified)
  • TooBigSelect (there is a limit to how much data can be selected)
  • InvalidUseOfNull (the schema has to say for each column whether null is permitted)
  • MixOfGroupFunctionAndFields (syntax can't mix these)
  • SyntaxError (an error in the SQL syntax)
  • TooLongString (there is a limit to what can be input)
  • WrongColumnName (the column name must exist in the referenced table/view)
  • DuplicateUnique (you can't insert a new row with same primary key as an existing row)
  • PrimaryCannotHaveNull (the primary key must be set to a specific value)
  • DivisionByZero (certain mathematical operations cannot be handled)

The table has two fields:

Column number # Column name Column type Properties Description
0 key integer Primary Key, Not NULL, No Default Value, An autoincrement integer for every SQL statement entered in the cache
1 statement varchar Not NULL, No Default Value, Contains the actual SQL statement that failed

SQLite Sequence

No relevant information on this table is known