Database management method, computer, sensor network system and time-series data management method

A computer for managing a database, comprising:

• a processor, and
• a memory connected to the processor,
• the database storing a plurality of pieces of compressed data which are compressed based on a given condition,
• the computer being configured to:
• analyze a query to the database which is received from a client computer coupled to the computer;
• generate a first inquiry for searching the database for at least one of the plurality of pieces of compressed data, based on a result of the analysis of the received query;
• generate a second inquiry for executing a search of a plurality of pieces of time-series data obtained from the at least one of the plurality of pieces of compressed data, which is a response result of the first inquiry, based on the result of the analysis of the received query;
• issue the first inquiry to the database and obtain the at least one of the plurality of pieces of compressed data from the database as the response result of the first inquiry;
• obtain the plurality of pieces of time-series data by decompressing the at least one of the plurality of pieces of compressed data which has been obtained as the response result of the first inquiry;
• execute the second inquiry for the obtained plurality of pieces of time-series data;
• extract a plurality of pieces of any data from the obtained plurality of pieces of time-series data, based on a response result of the second inquiry;
• and
• generate an output result by extracting data to be output to the client computer from the extracted plurality of pieces of any data.

A sensor network system comprising:

• a sensor for measuring a physical quantity of a sensing target;
• a computer for collecting, as time-series data, the physical quantity measured by the sensor;
• and
• a management server for storing the time-series data from the computer in a database,
• the computer having a first processor and a first memory connected to the first processor,
• the management server having a second processor and a second memory connected to the second processor,
• the computer and the management server being coupled to each other via a network,
• the database storing a plurality of pieces of compressed data which are obtained by compressing a plurality of pieces of time-series data based on a given condition,
• the management server being configured to:
• analyze a query to the database which is received from a client computer coupled to the management server via the network;
• generate a first inquiry for searching the database for at least one of the plurality of pieces of compressed data, based on a result of the analysis of the received query;
• generate a second inquiry for executing a search of the plurality of pieces of time-series data obtained from the at least one of the plurality of pieces of compressed data which is a response result of the first inquiry, based on the result of the analysis of the received query;
• issue the first inquiry to the database and obtain the at least one of the plurality of pieces of compressed data from the database as the response result of the first inquiry;
• obtain the plurality of pieces of time-series data by decompressing the at least one of the plurality of pieces of compressed data which has been obtained as the response result of the first inquiry;
• execute the second inquiry for the obtained plurality of pieces of time-series data;
• extract a plurality of pieces of any data from the obtained plurality of pieces of time-series data, based on a response result of the second inquiry;
• and
• generate an output result by extracting data to be output to the client computer from the extracted plurality of pieces of any data.