Indexes improve data retrieval performance. SAP Sybase IQ indexes differ from traditional indexes and are designed to accelerate queries in the data warehousing environment.
When you load data into a table, SAP Sybase IQ physically stores data by column rather than by row, for each column in the table. The column orientation gives IQ indexes important advantages over traditional row-based indexing.
The default column storage structure that SAP Sybase IQ creates for each column is an index that is optimized for storing and projecting data. The column indexes you define are created as part of each individual table.
Logically, you can still access the data as in traditional row-based SQL databases. Column storage structures your data according to the attributes you want to track. In a data warehousing environment, you typically look at specific attributes of thousands or millions of data rows, rather than complete, single rows of data. Column storage optimizes your ability to perform selections or calculations on specific attributes.