Composite indexes specify more than one column as the kay value. Maximum 16 Columns Maximum Total Length is 900 Bytes Define the Most Unique Column First The WHERE Clause Must Reference the first Column in the Index For the Query Optimizer to use the Composite Index

A composite index measures all common stocks listed on a given Exchange and any subgroup indices - that are a part of this index. The index tracks the change in market value of the exchange's common stocks, adjusted to eliminate the effects of new listings and de-listings. The market value of each stock is calculated by multiplying its price per share by the number of shares listed. The composite index is a fairly good indicator of general market strength.

An index that combines several variables into a single number. For example, The Human Development Index combines life expectancy, educational attainment, and GDP per head. Critics question the subjective nature of the approach in both deciding which elements are included and the relative weight given to each variable in the calculation of the index. Source: DFID Poverty:Bridging the Gap-Guidance Notes See also: Indicator