Traditionally relational data has been stored in rows—., as a sequence of tuples in which all the columns of each tuple are stored together on disk. This method has a long heritage back to early OLTP systems that introduced the “slotted page” layout still in common use today. However, analytical databases tend to have different access patterns than OLTP systems. Instead of seeing many single-row reads and writes, analytical databases must process larger, more complex queries that touch much larger volumes of data—., read-mostly with big scanning reads and infrequent batch appends of data. Vendors have taken a number of different.
