Data Compression

Essbase allows you to choose whether data blocks that are stored on disk are compressed, as well as which compression scheme to use. When data compression is enabled, Essbase compresses data blocks when it writes them out to disk. Essbase fully expands the compressed data blocks, including empty cells, when the blocks are swapped into the data cache.

Generally, data compression optimizes storage use. You can check compression efficiency by checking the compression ratio statistic. See Checking the Compression Ratio.

Essbase provides several options for data compression:

Because Essbase compresses data blocks as they are written to disk, it is possible for bitmap, RLE, and uncompressed data blocks to coexist in the same data file. Keep in mind the following rules:

You may want to disable data compression if blocks have very high density (90% or greater) and have few consecutive, repeating data values. Under these conditions, enabling compression consumes resources unnecessarily.