We propose a novel scheme that using multi-version structure to store the sensor data that need not only the latest version of data but also keep track of the old data in the flash memory. For sensor devices, it is important to preserve old version of sensor data for further queries. In our scheme, each sensor has different period and phase. We can query the historical data directly by a series of equations without using index structures to improve the query process. We can also query a period of version. Besides, we also consider the garbage collection to ensure that there are sufficient free blocks. We reclaim the old version of sensor data that accessed less frequently than new versions. Our scheme can reduce the number of page read and improve the write performance compare with traditional Multi-version B+-Tree index structures and Cluster-based Multi-version B+-Tree index structures.

We propose a novel scheme that using multi-version structure to store the sensor data that need not only the latest version of data but also keep track of the old data in the flash memory. For sensor devices, it is important to preserve old version of sensor data for further queries. In our scheme, each sensor has different period and phase. We can query the historical data directly by a series of equations without using index structures to improve the query process. We can also query a period of version. Besides, we also consider the garbage collection to ensure that there are sufficient free blocks. We reclaim the old version of sensor data that accessed less frequently than new versions. Our scheme can reduce the number of page read and improve the write performance compare with traditional Multi-version B+-Tree index structures and Cluster-based Multi-version B+-Tree index structures.

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