Sam Madden: September 2007 Archives

In regards to an earlier post about the advantages of compression in column-oriented databases, a commenter asked about maintaining the correspondence between columns in a column-oriented database. Sam Madden discusses how the issue isn't really "getting the data back in the original order" as much as it is ensuring that the system has a way of accessing records in other columns that correspond to a particular record in a sorted column. Continue reading "Follow up on compression post: Columns, indices, and sorting" »

One of the key performance features of column databases that Mike mentioned in his previous post was the aggressive use of data compression. In this post, we'll discuss how column-oriented databases are able to more effectively exploit compression than a typical row-oriented system. There are two key points: 1) Columns of data from the same attribute compress better than rows of tuples in a table; and 2) A well-architected database engine using appropriate compression techniques can operate directly on the compressed data, without decompressing it. Continue reading "Good things come in small packages: The advantage of compression in column databases" »