Different Types of Indexes and Their Uses
An index is, typically, a tree structure that allows a query to directly access a row in a table. Indexes can be classified based on their logical design or on the physical implementation.
Logical Index Classifications
The logical classification groups indexes together based on an application perspective of the index. The following list describes the various logical classification indexes:
Single column Has only one column in the index key; for example, claim_number might be the key for a claim table.
Concatenated Also known as composite indexes, these are indexes created on multiple columns in a table. The columns that are concatenated do not need to be in the same order as the columns appear in the ...
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