Preliminary information that still may change
VSCP tables is a built in feature of the VSCP daemon that let you collect data (measurements) from events in a SQL database over time automatically. The only thing you need to do is to add a VSCP decision matrix entry for the collection and a definition of your collection to the configuration.
You can build two types of tables
- Dynamic tables which works like any other database and save data in ever growing database.
- Static table which is a table with a static number of record. A table of this type can for example collect temperatures from temperature sensor over the last 24 hours.
- Max table which is a table that grows up to a specified size of elements and then clear all elements and start to fill the table again.
The collected data can be reached over
- The tcp/ip interface.
- The REST interface.
- The websocket interface.
Tables are stored in
- /srv/vscp/tables on Linux type systems.
- /programdata/vscp/tables on Windows systems. * In memory** on both Linux type and Windows systems.
The in memory type is very fast but is of course not persistent over time.
Configure a tables
You can define and configure tables in the main configuration file vscpd.xml or in the configuration database. Definitions in the xml file override conflicting definitions in the database configuration file.
Changes done in the VSCP administrative interface goes to the configuration database file.
The table definitions in the configuration file is described here.