Microsoft® TerraServer stores aerial, satellite, and topographic images of the earth in a SQL database available via the Internet. It is the world's largest online atlas, combining eight terabytes of image data from the United States Geological Survey (USGS) and SPIN-2. Internet browsers provide intuitive spatial and text interfaces to the data. Users need no special hardware, software, or knowledge to locate and browse imagery. This paper describes how terabytes of “Internet unfriendly” geo-spatial images were scrubbed and edited into hundreds of millions of “Internet friendly” image tiles and loaded into a SQL data warehouse. All meta-data and imagery are stored in the SQL database.

A new sort algorithm, called AlphaSort, demonstrates that commodity processors and disks can handle commercial batch workloads. Using Alpha AXP processors, commodity memory, and arrays of SCSI disks, AlphaSort runs the industry-standard sort benchmark in seven seconds. This beats the best published record on a 32-cpu 32-disk Hypercube by 8:1. On another benchmark, AlphaSort sorted more than a gigabyte in a minute.AlphaSort is a cache-sensitive memory-intensive sort algorithm. It uses file striping to get high disk bandwidth. It uses QuickSort to generate runs and uses replacement-selection to merge the runs. It uses shared memory multiprocessors to break the sort into subsort chores.Because startup times are becoming a significant part of the total time, we propose two new benchmarks: (1) Minutesort: how much can you sort in a minute, and (2) DollarSort: how much can you sort for a dollar.