Vertical / Column-based storage
Due to EXASolution's specialization on the data warehousing it benefits from the column-wise data storage reducing the number of IO operations and the overall amount of processed data. Typically queries in a data warehouse access only few columns (f.e. at joining tables).
In order to optimize access to the hard disk, columns are partitioned into blocks. This facilitates maximum throughput and prevents unnecessary data from being imported. Gaps can emerge in the blocks as a result of various operations (e.g. deletions or updates); however, the system automatically conducts a defragmentation if certain limits are exceeded.
Data compression
To optimize RAM utilization, table data is compressed element by element already in main memory; on basis of the data types and content of the columns, the system automatically selects a sufficiently effective compression algorithm. Compression is fully transparent to the user.
