crucial to fit data in memory  automatic lossless compression  Sub-problems: #rows>>#cols, column correlation, column characteristics  column-wise compression w/ heterogeneous encoding formats Time Prog- Linear Algebra  Data characteristics inspired overall design of encoding schemes  Initially slow compression  dedicated sampling schemes and estimators  Initially slow compressed operations  cache-conscious it's an interesting problem General-purpose, heavy- and lightweight compression techniques struggle to achieve both good compression ratios and fast decompression speed to enable block-wise uncompressed

characteristics  Systematic evaluation w/ datasize, sparsity, etc  Inappropriate for certain topics: compression, ML accuracy  “Real” Data Repositories  Wide selection of available datasets w/ different characteristics Boehm, Graz University of Technology, WS 2021/22 Baselines  #1 Primary Baseline  Existing algorithm or system infrastructure  Main comparison point, usually with same runtime operations  Beware:

Relevant Work  Motivation  Some research areas might be very large (e.g., index structures, compression)  How do you find relevant scientific papers/thesis via multiple channels  By Venue/Year  particularly poor. We use index structures like b-trees, tries, and hash tables; as well as compression techniques like run-length encoding, dictionary encoding, and null suppression. A woman without Figure~\ref{fig:exp1} Equation~\eqref{eq:e1} employ general-purpose compression techniques employ a general-purpose compression technique Each entry ???????????????????????? can be expressed over

Convert the phrase to plain ASCII and remove any apostrophes. For example, “Müller’s algorithm” might become “Muellers algorithm”. 2. Divide this result into words, splitting on spaces and any remaining punc-

responsibility for identifying the hash inputs with re- sponsibility for executing the hashing algorithm itself. The type author has to be responsible for the former, but the latter requires expertise